Merge pull request #1608 from GriffinRichards/fix-fieldmap

Fix some incorrect fieldmap names

34 files changed, 461 insertions, 570 deletions

diff --git a/common_syms/overworld.txt b/common_syms/overworld.txt
index e136f5444..dcada0bbe 100644
--- a/common_syms/overworld.txt
+++ b/common_syms/overworld.txt
@@ -1,6 +1,6 @@
-gBGTilemapBuffers1
-gBGTilemapBuffers2
-gBGTilemapBuffers3
+gOverworldTilemapBuffer_Bg2
+gOverworldTilemapBuffer_Bg1
+gOverworldTilemapBuffer_Bg3
 gHeldKeyCodeToSend
 gFieldCallback
 gFieldCallback2
diff --git a/gflib/bg.c b/gflib/bg.c
index c96bcbc23..6e97be207 100644
--- a/gflib/bg.c
+++ b/gflib/bg.c
@@ -1053,7 +1053,7 @@ void WriteSequenceToBgTilemapBuffer(u8 bg, u16 firstTileNum, u8 x, u8 y, u8 widt
                 for (x16 = x; x16 < (x + width); x16++)
                 {
                     CopyTileMapEntry(&firstTileNum, &((u16*)sGpuBgConfigs2[bg].tilemap)[(u16)GetTileMapIndexFromCoords(x16, y16, attribute, mode, mode2)], paletteSlot, 0, 0);
-                    firstTileNum = (firstTileNum & (METATILE_COLLISION_MASK | METATILE_ELEVATION_MASK)) + ((firstTileNum + tileNumDelta) & METATILE_ID_MASK);
+                    firstTileNum = (firstTileNum & (MAPGRID_COLLISION_MASK | MAPGRID_ELEVATION_MASK)) + ((firstTileNum + tileNumDelta) & MAPGRID_METATILE_ID_MASK);
                 }
             }
             break;
@@ -1064,7 +1064,7 @@ void WriteSequenceToBgTilemapBuffer(u8 bg, u16 firstTileNum, u8 x, u8 y, u8 widt
                 for (x16 = x; x16 < (x + width); x16++)
                 {
                     ((u8*)sGpuBgConfigs2[bg].tilemap)[(y16 * mode3) + x16] = firstTileNum;
-                    firstTileNum = (firstTileNum & (METATILE_COLLISION_MASK | METATILE_ELEVATION_MASK)) + ((firstTileNum + tileNumDelta) & METATILE_ID_MASK);
+                    firstTileNum = (firstTileNum & (MAPGRID_COLLISION_MASK | MAPGRID_ELEVATION_MASK)) + ((firstTileNum + tileNumDelta) & MAPGRID_METATILE_ID_MASK);
                 }
             }
             break;
diff --git a/include/constants/metatile_behaviors.h b/include/constants/metatile_behaviors.h
index 5f37713f3..86f35ce50 100755
--- a/include/constants/metatile_behaviors.h
+++ b/include/constants/metatile_behaviors.h
@@ -9,7 +9,7 @@
 #define MB_UNUSED_05 0x05
 #define MB_DEEP_SAND 0x06
 #define MB_SHORT_GRASS 0x07
-#define MB_UNUSED_CAVE 0x08
+#define MB_CAVE 0x08
 #define MB_LONG_GRASS_SOUTH_EDGE 0x09
 #define MB_NO_RUNNING 0x0A
 #define MB_INDOOR_ENCOUNTER 0x0B
@@ -179,8 +179,8 @@
 #define MB_UNUSED_AF 0xAF
 #define MB_SECRET_BASE_PC 0xB0
 #define MB_SECRET_BASE_REGISTER_PC 0xB1
-#define MB_SECRET_BASE_UNUSED 0xB2
-#define MB_BLOCK_DECORATION 0xB3
+#define MB_SECRET_BASE_SCENERY 0xB2
+#define MB_SECRET_BASE_TRAINER_SPOT 0xB3
 #define MB_SECRET_BASE_DECORATION 0xB4
 #define MB_HOLDS_SMALL_DECORATION 0xB5
 #define MB_UNUSED_B6 0xB6
@@ -241,6 +241,9 @@
 #define MB_UNUSED_ED 0xED
 #define MB_UNUSED_EE 0xEE
 #define MB_UNUSED_EF 0xEF
+
+#define NUM_METATILE_BEHAVIORS 0xF0
+
 #define MB_INVALID   0xFF
 
 #endif // GUARD_METATILE_BEHAVIORS_H
diff --git a/include/event_object_movement.h b/include/event_object_movement.h
index bd8232027..d31802a67 100644
--- a/include/event_object_movement.h
+++ b/include/event_object_movement.h
@@ -98,7 +98,7 @@ void ObjectEventClearHeldMovementIfActive(struct ObjectEvent *);
 void TrySpawnObjectEvents(s16, s16);
 u8 CreateObjectGraphicsSprite(u16, void (*)(struct Sprite *), s16 x, s16 y, u8 subpriority);
 u8 TrySpawnObjectEvent(u8, u8, u8);
-u8 SpawnSpecialObjectEventParameterized(u8 graphicsId, u8 movementBehavior, u8 localId, s16 x, s16 y, u8 z);
+u8 SpawnSpecialObjectEventParameterized(u8 graphicsId, u8 movementBehavior, u8 localId, s16 x, s16 y, u8 elevation);
 u8 SpawnSpecialObjectEvent(struct ObjectEventTemplate *);
 void SetSpritePosToMapCoords(s16, s16, s16 *, s16 *);
 void CameraObjectReset1(void);
@@ -128,7 +128,7 @@ u8 GetCollisionAtCoords(struct ObjectEvent *, s16, s16, u32);
 void MoveCoords(u8, s16 *, s16 *);
 bool8 ObjectEventIsHeldMovementActive(struct ObjectEvent *);
 u8 ObjectEventClearHeldMovementIfFinished(struct ObjectEvent *);
-u8 GetObjectEventIdByXYZ(u16 x, u16 y, u8 z);
+u8 GetObjectEventIdByPosition(u16 x, u16 y, u8 elevation);
 void SetTrainerMovementType(struct ObjectEvent *objectEvent, u8 movementType);
 u8 GetTrainerFacingDirectionMovementType(u8 direction);
 const u8 *GetObjectEventScriptPointerByObjectEventId(u8 objectEventId);
@@ -162,17 +162,15 @@ u8 ObjectEventCheckHeldMovementStatus(struct ObjectEvent *objectEvent);
 u8 ObjectEventGetHeldMovementActionId(struct ObjectEvent *objectEvent);
 void TryOverrideTemplateCoordsForObjectEvent(const struct ObjectEvent *objectEvent, u8 movementType);
 void OverrideTemplateCoordsForObjectEvent(const struct ObjectEvent *objectEvent);
-void ShiftStillObjectEventCoords(struct ObjectEvent *pObject);
-void ObjectEventMoveDestCoords(struct ObjectEvent *pObject, u32 unk_19, s16 *pInt, s16 *pInt1);
+void ShiftStillObjectEventCoords(struct ObjectEvent *objEvent);
+void ObjectEventMoveDestCoords(struct ObjectEvent *objEvent, u32 direction, s16 *x, s16 *y);
 u8 AddCameraObject(u8 linkedSpriteId);
 void UpdateObjectEventsForCameraUpdate(s16 x, s16 y);
 u8 GetWalkSlowMovementAction(u32);
 u8 GetJumpMovementAction(u32);
-bool8 AreZCoordsCompatible(u8, u8);
-u8 ZCoordToPriority(u8);
-void ObjectEventUpdateZCoord(struct ObjectEvent *pObject);
-void SetObjectSubpriorityByZCoord(u8, struct Sprite *, u8);
-bool8 IsZCoordMismatchAt(u8, s16, s16);
+u8 ElevationToPriority(u8);
+void ObjectEventUpdateElevation(struct ObjectEvent *objEvent);
+void SetObjectSubpriorityByElevation(u8, struct Sprite *, u8);
 void UnfreezeObjectEvent(struct ObjectEvent *);
 u8 FindLockedObjectEventIndex(struct ObjectEvent *);
 void SetAndStartSpriteAnim(struct Sprite *, u8, u8);
@@ -413,7 +411,7 @@ u8 MovementType_Invisible_Step0(struct ObjectEvent *, struct Sprite *);
 u8 MovementType_Invisible_Step1(struct ObjectEvent *, struct Sprite *);
 u8 MovementType_Invisible_Step2(struct ObjectEvent *, struct Sprite *);
 
-u8 CreateVirtualObject(u8 graphicsId, u8 virtualObjId, s16 x, s16 y, u8 z, u8 direction);
+u8 CreateVirtualObject(u8 graphicsId, u8 virtualObjId, s16 x, s16 y, u8 elevation, u8 direction);
 void TurnVirtualObject(u8 virtualObjId, u8 direction);
 void SetVirtualObjectGraphics(u8 virtualObjId, u8 graphicsId);
 void SetVirtualObjectInvisibility(u8 virtualObjId, bool32 invisible);
diff --git a/include/field_player_avatar.h b/include/field_player_avatar.h
index 823564f22..d382de08c 100644
--- a/include/field_player_avatar.h
+++ b/include/field_player_avatar.h
@@ -30,7 +30,7 @@ void PlayerSetAnimId(u8 a, u8 b);
 bool8 IsPlayerCollidingWithFarawayIslandMew(u8 direction);
 void PlayerOnBikeCollideWithFarawayIslandMew(u8 direction);
 u8 CheckForObjectEventCollision(struct ObjectEvent *a, s16 b, s16 c, u8 d, u8 e);
-u8 PlayerGetZCoord(void);
+u8 PlayerGetElevation(void);
 void SetPlayerAvatarTransitionFlags(u16 a);
 void CancelPlayerForcedMovement(void);
 void InitPlayerAvatar(s16 a, s16 b, u8 c, u8 d);
diff --git a/include/fieldmap.h b/include/fieldmap.h
index aabfce461..e7497f7bd 100644
--- a/include/fieldmap.h
+++ b/include/fieldmap.h
@@ -29,10 +29,10 @@ void GetCameraCoords(u16*, u16*);
 bool8 MapGridIsImpassableAt(int, int);
 int GetMapBorderIdAt(int x, int y);
 bool32 CanCameraMoveInDirection(int direction);
-u16 GetBehaviorByMetatileId(u16 metatileId);
+u16 GetMetatileAttributesById(u16 metatileId);
 void GetCameraFocusCoords(u16 *x, u16 *y);
 u8 MapGridGetMetatileLayerTypeAt(int x, int y);
-u8 MapGridGetZCoordAt(int x, int y);
+u8 MapGridGetElevationAt(int x, int y);
 bool8 CameraMove(int deltaX, int deltaY);
 void SaveMapView(void);
 void SetCameraFocusCoords(u16 x, u16 y);
diff --git a/include/global.fieldmap.h b/include/global.fieldmap.h
index 33be942c8..21c354658 100644
--- a/include/global.fieldmap.h
+++ b/include/global.fieldmap.h
@@ -1,13 +1,30 @@
 #ifndef GUARD_GLOBAL_FIELDMAP_H
 #define GUARD_GLOBAL_FIELDMAP_H
 
-#define METATILE_BEHAVIOR_MASK 0x00FF
-#define METATILE_COLLISION_MASK 0x0C00
-#define METATILE_ID_MASK 0x03FF
-#define METATILE_ID_UNDEFINED 0x03FF
-#define METATILE_ELEVATION_SHIFT 12
-#define METATILE_COLLISION_SHIFT 10
-#define METATILE_ELEVATION_MASK 0xF000
+// Masks/shifts for blocks in the map grid
+// Map grid blocks consist of a 10 bit metatile id, a 2 bit collision value, and a 4 bit elevation value
+// This is the data stored in each data/layouts/*/map.bin file
+#define MAPGRID_METATILE_ID_MASK 0x03FF // Bits 1-10
+#define MAPGRID_COLLISION_MASK   0x0C00 // Bits 11-12
+#define MAPGRID_ELEVATION_MASK   0xF000 // Bits 13-16
+#define MAPGRID_COLLISION_SHIFT  10
+#define MAPGRID_ELEVATION_SHIFT  12
+
+// An undefined map grid block has all metatile id bits set and nothing else
+#define MAPGRID_UNDEFINED   MAPGRID_METATILE_ID_MASK
+
+// Masks/shifts for metatile attributes
+// Metatile attributes consist of an 8 bit behavior value, 4 unused bits, and a 4 bit layer type value
+// This is the data stored in each data/tilesets/*/*/metatile_attributes.bin file
+#define METATILE_ATTR_BEHAVIOR_MASK 0x00FF // Bits 1-8
+#define METATILE_ATTR_LAYER_MASK    0xF000 // Bits 13-16
+#define METATILE_ATTR_LAYER_SHIFT   12
+
+enum {
+    METATILE_LAYER_TYPE_NORMAL,  // Metatile uses middle and top bg layers
+    METATILE_LAYER_TYPE_COVERED, // Metatile uses bottom and middle bg layers
+    METATILE_LAYER_TYPE_SPLIT,   // Metatile uses bottom and top bg layers
+};
 
 #define METATILE_ID(tileset, name) (METATILE_##tileset##_##name)
 
diff --git a/include/global.h b/include/global.h
index 51ecbcbce..0122ecd5c 100644
--- a/include/global.h
+++ b/include/global.h
@@ -1022,7 +1022,7 @@ struct MapPosition
 {
     s16 x;
     s16 y;
-    s8 height;
+    s8 elevation;
 };
 
 #endif // GUARD_GLOBAL_H
diff --git a/include/metatile_behavior.h b/include/metatile_behavior.h
index 5895426cf..c2d0d23ee 100644
--- a/include/metatile_behavior.h
+++ b/include/metatile_behavior.h
@@ -57,7 +57,7 @@ bool8 MetatileBehavior_IsSecretBaseTree(u8);
 bool8 MetatileBehavior_IsSecretBaseShrub(u8);
 bool8 MetatileBehavior_IsSecretBasePC(u8);
 bool8 MetatileBehavior_IsRecordMixingSecretBasePC(u8);
-bool8 MetatileBehavior_IsBlockDecoration(u8);
+bool8 MetatileBehavior_IsSecretBaseTrainerSpot(u8);
 bool8 MetatileBehavior_IsSecretBaseImpassable(u8);
 bool8 MetatileBehavior_IsSecretBaseDecorationBase(u8);
 bool8 MetatileBehavior_IsSecretBasePoster(u8);
diff --git a/include/overworld.h b/include/overworld.h
index 04b61f7fd..b8794ea70 100644
--- a/include/overworld.h
+++ b/include/overworld.h
@@ -40,20 +40,18 @@ struct LinkPlayerObjectEvent
     u8 movementMode;
 };
 
-// Exported RAM declarations
 extern struct WarpData gLastUsedWarp;
 extern struct LinkPlayerObjectEvent gLinkPlayerObjectEvents[4];
 
-extern u16 *gBGTilemapBuffers1;
-extern u16 *gBGTilemapBuffers2;
-extern u16 *gBGTilemapBuffers3;
+extern u16 *gOverworldTilemapBuffer_Bg2;
+extern u16 *gOverworldTilemapBuffer_Bg1;
+extern u16 *gOverworldTilemapBuffer_Bg3;
 extern u16 gHeldKeyCodeToSend;
 extern void (*gFieldCallback)(void);
 extern bool8 (*gFieldCallback2)(void);
 extern u8 gLocalLinkPlayerId;
 extern u8 gFieldLinkPlayerCount;
 
-// Exported ROM declarations
 extern const struct UCoords32 gDirectionToVectors[];
 
 void DoWhiteOut(void);
diff --git a/src/battle_pyramid.c b/src/battle_pyramid.c
index b10690ce4..154760396 100644
--- a/src/battle_pyramid.c
+++ b/src/battle_pyramid.c
@@ -1239,7 +1239,7 @@ static u8 GetPostBattleDirectionHintTextIndex(int *hintType, u8 minDistanceForEx
     {
         for (x = 0; x < 32; x++)
         {
-            if ((map[x] & METATILE_ID_MASK) == METATILE_BattlePyramid_Exit)
+            if ((map[x] & MAPGRID_METATILE_ID_MASK) == METATILE_BattlePyramid_Exit)
             {
                 x += MAP_OFFSET - gObjectEvents[gSelectedObjectEvent].initialCoords.x;
                 y += MAP_OFFSET - gObjectEvents[gSelectedObjectEvent].initialCoords.y;
@@ -1545,7 +1545,7 @@ void GenerateBattlePyramidFloorLayout(u16 *backupMapData, bool8 setPlayerPositio
         {
             for (x = 0; x < mapLayout->width; x++)
             {
-                if ((layoutMap[x] & METATILE_ID_MASK) != METATILE_BattlePyramid_Exit)
+                if ((layoutMap[x] & MAPGRID_METATILE_ID_MASK) != METATILE_BattlePyramid_Exit)
                 {
                     map[x] = layoutMap[x];
                 }
@@ -1556,7 +1556,7 @@ void GenerateBattlePyramidFloorLayout(u16 *backupMapData, bool8 setPlayerPositio
                         gSaveBlock1Ptr->pos.x = (mapLayout->width * (i % 4)) + x;
                         gSaveBlock1Ptr->pos.y = (mapLayout->height * (i / 4)) + y;
                     }
-                    map[x] = (layoutMap[x] & (METATILE_ELEVATION_MASK | METATILE_COLLISION_MASK)) | METATILE_BattlePyramid_Floor;
+                    map[x] = (layoutMap[x] & (MAPGRID_ELEVATION_MASK | MAPGRID_COLLISION_MASK)) | METATILE_BattlePyramid_Floor;
                 }
                 else
                 {
diff --git a/src/bike.c b/src/bike.c
index c99d514cb..ae30ce288 100644
--- a/src/bike.c
+++ b/src/bike.c
@@ -900,7 +900,7 @@ static bool8 IsRunningDisallowedByMetatile(u8 tile)
 {
     if (MetatileBehavior_IsRunningDisallowed(tile))
         return TRUE;
-    if (MetatileBehavior_IsFortreeBridge(tile) && (PlayerGetZCoord() & 1) == 0)
+    if (MetatileBehavior_IsFortreeBridge(tile) && (PlayerGetElevation() & 1) == 0)
         return TRUE;
     return FALSE;
 }
diff --git a/src/braille_puzzles.c b/src/braille_puzzles.c
index 26caa830d..876e6b4a7 100644
--- a/src/braille_puzzles.c
+++ b/src/braille_puzzles.c
@@ -80,9 +80,9 @@ void DoBrailleDigEffect(void)
     MapGridSetMetatileIdAt( 9 + MAP_OFFSET, 1 + MAP_OFFSET, METATILE_Cave_SealedChamberEntrance_TopLeft);
     MapGridSetMetatileIdAt(10 + MAP_OFFSET, 1 + MAP_OFFSET, METATILE_Cave_SealedChamberEntrance_TopMid);
     MapGridSetMetatileIdAt(11 + MAP_OFFSET, 1 + MAP_OFFSET, METATILE_Cave_SealedChamberEntrance_TopRight);
-    MapGridSetMetatileIdAt( 9 + MAP_OFFSET, 2 + MAP_OFFSET, METATILE_Cave_SealedChamberEntrance_BottomLeft | METATILE_COLLISION_MASK);
+    MapGridSetMetatileIdAt( 9 + MAP_OFFSET, 2 + MAP_OFFSET, METATILE_Cave_SealedChamberEntrance_BottomLeft | MAPGRID_COLLISION_MASK);
     MapGridSetMetatileIdAt(10 + MAP_OFFSET, 2 + MAP_OFFSET, METATILE_Cave_SealedChamberEntrance_BottomMid);
-    MapGridSetMetatileIdAt(11 + MAP_OFFSET, 2 + MAP_OFFSET, METATILE_Cave_SealedChamberEntrance_BottomRight | METATILE_COLLISION_MASK);
+    MapGridSetMetatileIdAt(11 + MAP_OFFSET, 2 + MAP_OFFSET, METATILE_Cave_SealedChamberEntrance_BottomRight | MAPGRID_COLLISION_MASK);
     DrawWholeMapView();
     PlaySE(SE_BANG);
     FlagSet(FLAG_SYS_BRAILLE_DIG);
@@ -207,9 +207,9 @@ static void DoBrailleRegirockEffect(void)
     MapGridSetMetatileIdAt(7 + MAP_OFFSET, 19 + MAP_OFFSET, METATILE_Cave_SealedChamberEntrance_TopLeft);
     MapGridSetMetatileIdAt(8 + MAP_OFFSET, 19 + MAP_OFFSET, METATILE_Cave_SealedChamberEntrance_TopMid);
     MapGridSetMetatileIdAt(9 + MAP_OFFSET, 19 + MAP_OFFSET, METATILE_Cave_SealedChamberEntrance_TopRight);
-    MapGridSetMetatileIdAt(7 + MAP_OFFSET, 20 + MAP_OFFSET, METATILE_Cave_SealedChamberEntrance_BottomLeft | METATILE_COLLISION_MASK);
+    MapGridSetMetatileIdAt(7 + MAP_OFFSET, 20 + MAP_OFFSET, METATILE_Cave_SealedChamberEntrance_BottomLeft | MAPGRID_COLLISION_MASK);
     MapGridSetMetatileIdAt(8 + MAP_OFFSET, 20 + MAP_OFFSET, METATILE_Cave_SealedChamberEntrance_BottomMid);
-    MapGridSetMetatileIdAt(9 + MAP_OFFSET, 20 + MAP_OFFSET, METATILE_Cave_SealedChamberEntrance_BottomRight | METATILE_COLLISION_MASK);
+    MapGridSetMetatileIdAt(9 + MAP_OFFSET, 20 + MAP_OFFSET, METATILE_Cave_SealedChamberEntrance_BottomRight | MAPGRID_COLLISION_MASK);
     DrawWholeMapView();
     PlaySE(SE_BANG);
     FlagSet(FLAG_SYS_REGIROCK_PUZZLE_COMPLETED);
@@ -246,9 +246,9 @@ static void DoBrailleRegisteelEffect(void)
     MapGridSetMetatileIdAt(7 + MAP_OFFSET, 19 + MAP_OFFSET, METATILE_Cave_SealedChamberEntrance_TopLeft);
     MapGridSetMetatileIdAt(8 + MAP_OFFSET, 19 + MAP_OFFSET, METATILE_Cave_SealedChamberEntrance_TopMid);
     MapGridSetMetatileIdAt(9 + MAP_OFFSET, 19 + MAP_OFFSET, METATILE_Cave_SealedChamberEntrance_TopRight);
-    MapGridSetMetatileIdAt(7 + MAP_OFFSET, 20 + MAP_OFFSET, METATILE_Cave_SealedChamberEntrance_BottomLeft | METATILE_COLLISION_MASK);
+    MapGridSetMetatileIdAt(7 + MAP_OFFSET, 20 + MAP_OFFSET, METATILE_Cave_SealedChamberEntrance_BottomLeft | MAPGRID_COLLISION_MASK);
     MapGridSetMetatileIdAt(8 + MAP_OFFSET, 20 + MAP_OFFSET, METATILE_Cave_SealedChamberEntrance_BottomMid);
-    MapGridSetMetatileIdAt(9 + MAP_OFFSET, 20 + MAP_OFFSET, METATILE_Cave_SealedChamberEntrance_BottomRight | METATILE_COLLISION_MASK);
+    MapGridSetMetatileIdAt(9 + MAP_OFFSET, 20 + MAP_OFFSET, METATILE_Cave_SealedChamberEntrance_BottomRight | MAPGRID_COLLISION_MASK);
     DrawWholeMapView();
     PlaySE(SE_BANG);
     FlagSet(FLAG_SYS_REGISTEEL_PUZZLE_COMPLETED);
diff --git a/src/decoration.c b/src/decoration.c
index 85a74ed9d..7e102251a 100644
--- a/src/decoration.c
+++ b/src/decoration.c
@@ -1185,10 +1185,10 @@ static u16 GetDecorationElevation(u8 decoration, u8 tileIndex)
     switch (decoration)
     {
     case DECOR_STAND:
-        elevation = sDecorationStandElevations[tileIndex] << METATILE_ELEVATION_SHIFT;
+        elevation = sDecorationStandElevations[tileIndex] << MAPGRID_ELEVATION_SHIFT;
         return elevation;
     case DECOR_SLIDE:
-        elevation = sDecorationSlideElevation[tileIndex] << METATILE_ELEVATION_SHIFT;
+        elevation = sDecorationSlideElevation[tileIndex] << MAPGRID_ELEVATION_SHIFT;
         return elevation;
     default:
         return elevation;
@@ -1199,7 +1199,7 @@ static void ShowDecorationOnMap_(u16 mapX, u16 mapY, u8 decWidth, u8 decHeight,
 {
     u16 i, j;
     s16 x, y;
-    u16 behavior;
+    u16 attributes;
     u16 impassableFlag;
     u16 overlapsWall;
     u16 elevation;
@@ -1210,9 +1210,10 @@ static void ShowDecorationOnMap_(u16 mapX, u16 mapY, u8 decWidth, u8 decHeight,
         for (i = 0; i < decWidth; i++)
         {
             x = mapX + i;
-            behavior = GetBehaviorByMetatileId(NUM_TILES_IN_PRIMARY + gDecorations[decoration].tiles[j * decWidth + i]);
-            if (MetatileBehavior_IsSecretBaseImpassable(behavior) == TRUE || (gDecorations[decoration].permission != DECORPERM_PASS_FLOOR && (behavior >> METATILE_ELEVATION_SHIFT)))
-                impassableFlag = METATILE_COLLISION_MASK;
+            attributes = GetMetatileAttributesById(NUM_TILES_IN_PRIMARY + gDecorations[decoration].tiles[j * decWidth + i]);
+            if (MetatileBehavior_IsSecretBaseImpassable(attributes & METATILE_ATTR_BEHAVIOR_MASK) == TRUE 
+             || (gDecorations[decoration].permission != DECORPERM_PASS_FLOOR && (attributes >> METATILE_ATTR_LAYER_SHIFT) != METATILE_LAYER_TYPE_NORMAL))
+                impassableFlag = MAPGRID_COLLISION_MASK;
             else
                 impassableFlag = 0;
 
@@ -1471,24 +1472,26 @@ static void AttemptCancelPlaceDecoration(u8 taskId)
     DisplayItemMessageOnField(taskId, gStringVar4, CancelDecoratingPrompt);
 }
 
-// Note: behaviorBy is pre-anded with METATILE_ELEVATION_MASK.
-static bool8 IsNonBlockNonElevated(u8 behaviorAt, u16 behaviorBy)
+static bool8 IsSecretBaseTrainerSpot(u8 behaviorAt, u16 layerType)
 {
-    if (MetatileBehavior_IsBlockDecoration(behaviorAt) != TRUE || behaviorBy != 0)
+    if (!(MetatileBehavior_IsSecretBaseTrainerSpot(behaviorAt) == TRUE && layerType == METATILE_LAYER_TYPE_NORMAL))
         return FALSE;
     return TRUE;
 }
 
-static bool8 IsntInitialPosition(u8 taskId, s16 x, s16 y, u16 behaviorBy)
+// Can't place decoration where the player was standing when they interacted with the PC
+static bool8 IsntInitialPosition(u8 taskId, s16 x, s16 y, u16 layerType)
 {
-    if (x == gTasks[taskId].tInitialX + MAP_OFFSET && y == gTasks[taskId].tInitialY + MAP_OFFSET && behaviorBy != 0)
+    if (x == gTasks[taskId].tInitialX + MAP_OFFSET 
+     && y == gTasks[taskId].tInitialY + MAP_OFFSET
+     && layerType != METATILE_LAYER_TYPE_NORMAL)
         return FALSE;
     return TRUE;
 }
 
 static bool8 IsFloorOrBoardAndHole(u16 behaviorAt, const struct Decoration *decoration)
 {
-    if (MetatileBehavior_IsBlockDecoration(behaviorAt) != TRUE)
+    if (MetatileBehavior_IsSecretBaseTrainerSpot(behaviorAt) != TRUE)
     {
         if (decoration->id == DECOR_SOLID_BOARD && MetatileBehavior_IsSecretBaseHole(behaviorAt) == TRUE)
             return TRUE;
@@ -1505,7 +1508,7 @@ static bool8 CanPlaceDecoration(u8 taskId, const struct Decoration *decoration)
     u8 i;
     u8 j;
     u8 behaviorAt;
-    u16 behaviorBy;
+    u16 layerType;
     u8 mapY;
     u8 mapX;
     s16 curY;
@@ -1524,14 +1527,14 @@ static bool8 CanPlaceDecoration(u8 taskId, const struct Decoration *decoration)
             {
                 curX = gTasks[taskId].tCursorX + j;
                 behaviorAt = MapGridGetMetatileBehaviorAt(curX, curY);
-                behaviorBy = GetBehaviorByMetatileId(NUM_TILES_IN_PRIMARY + decoration->tiles[(mapY - 1 - i) * mapX + j]) & METATILE_ELEVATION_MASK;
+                layerType = GetMetatileAttributesById(NUM_TILES_IN_PRIMARY + decoration->tiles[(mapY - 1 - i) * mapX + j]) & METATILE_ATTR_LAYER_MASK;
                 if (!IsFloorOrBoardAndHole(behaviorAt, decoration))
                     return FALSE;
 
-                if (!IsntInitialPosition(taskId, curX, curY, behaviorBy))
+                if (!IsntInitialPosition(taskId, curX, curY, layerType))
                     return FALSE;
 
-                behaviorAt = GetObjectEventIdByXYZ(curX, curY, 0);
+                behaviorAt = GetObjectEventIdByPosition(curX, curY, 0);
                 if (behaviorAt != 0 && behaviorAt != OBJECT_EVENTS_COUNT)
                     return FALSE;
             }
@@ -1545,14 +1548,14 @@ static bool8 CanPlaceDecoration(u8 taskId, const struct Decoration *decoration)
             {
                 curX = gTasks[taskId].tCursorX + j;
                 behaviorAt = MapGridGetMetatileBehaviorAt(curX, curY);
-                behaviorBy = GetBehaviorByMetatileId(NUM_TILES_IN_PRIMARY + decoration->tiles[(mapY - 1 - i) * mapX + j]) & METATILE_ELEVATION_MASK;
-                if (!MetatileBehavior_IsNormal(behaviorAt) && !IsNonBlockNonElevated(behaviorAt, behaviorBy))
+                layerType = GetMetatileAttributesById(NUM_TILES_IN_PRIMARY + decoration->tiles[(mapY - 1 - i) * mapX + j]) & METATILE_ATTR_LAYER_MASK;
+                if (!MetatileBehavior_IsNormal(behaviorAt) && !IsSecretBaseTrainerSpot(behaviorAt, layerType))
                     return FALSE;
 
-                if (!IsntInitialPosition(taskId, curX, curY, behaviorBy))
+                if (!IsntInitialPosition(taskId, curX, curY, layerType))
                     return FALSE;
 
-                if (GetObjectEventIdByXYZ(curX, curY, 0) != OBJECT_EVENTS_COUNT)
+                if (GetObjectEventIdByPosition(curX, curY, 0) != OBJECT_EVENTS_COUNT)
                     return FALSE;
             }
         }
@@ -1562,14 +1565,14 @@ static bool8 CanPlaceDecoration(u8 taskId, const struct Decoration *decoration)
         {
             curX = gTasks[taskId].tCursorX + j;
             behaviorAt = MapGridGetMetatileBehaviorAt(curX, curY);
-            behaviorBy = GetBehaviorByMetatileId(NUM_TILES_IN_PRIMARY + decoration->tiles[j]) & METATILE_ELEVATION_MASK;
+            layerType = GetMetatileAttributesById(NUM_TILES_IN_PRIMARY + decoration->tiles[j]) & METATILE_ATTR_LAYER_MASK;
             if (!MetatileBehavior_IsNormal(behaviorAt) && !MetatileBehavior_IsSecretBaseNorthWall(behaviorAt))
                 return FALSE;
 
-            if (!IsntInitialPosition(taskId, curX, curY, behaviorBy))
+            if (!IsntInitialPosition(taskId, curX, curY, layerType))
                 return FALSE;
 
-            behaviorAt = GetObjectEventIdByXYZ(curX, curY, 0);
+            behaviorAt = GetObjectEventIdByPosition(curX, curY, 0);
             if (behaviorAt != 0 && behaviorAt != OBJECT_EVENTS_COUNT)
                 return FALSE;
         }
@@ -1606,7 +1609,7 @@ static bool8 CanPlaceDecoration(u8 taskId, const struct Decoration *decoration)
                     return FALSE;
             }
 
-            if (GetObjectEventIdByXYZ(curX, curY, 0) != OBJECT_EVENTS_COUNT)
+            if (GetObjectEventIdByPosition(curX, curY, 0) != OBJECT_EVENTS_COUNT)
                 return FALSE;
         }
         break;
diff --git a/src/event_object_movement.c b/src/event_object_movement.c
index 2c7ceedf4..4bd8d5603 100644
--- a/src/event_object_movement.c
+++ b/src/event_object_movement.c
@@ -110,7 +110,7 @@ static void GetGroundEffectFlags_Seaweed(struct ObjectEvent*, u32*);
 static void GetGroundEffectFlags_JumpLanding(struct ObjectEvent*, u32*);
 static u8 ObjectEventGetNearbyReflectionType(struct ObjectEvent*);
 static u8 GetReflectionTypeByMetatileBehavior(u32);
-static void InitObjectPriorityByZCoord(struct Sprite *sprite, u8 z);
+static void InitObjectPriorityByElevation(struct Sprite *, u8);
 static void ObjectEventUpdateSubpriority(struct ObjectEvent*, struct Sprite*);
 static void DoTracksGroundEffect_None(struct ObjectEvent*, struct Sprite*, u8);
 static void DoTracksGroundEffect_Footprints(struct ObjectEvent*, struct Sprite*, u8);
@@ -142,27 +142,29 @@ static void ResetObjectEventFldEffData(struct ObjectEvent *);
 static u8 LoadSpritePaletteIfTagExists(const struct SpritePalette *);
 static u8 FindObjectEventPaletteIndexByTag(u16);
 static void _PatchObjectPalette(u16, u8);
-static bool8 ObjectEventDoesZCoordMatch(struct ObjectEvent *, u8);
+static bool8 ObjectEventDoesElevationMatch(struct ObjectEvent *, u8);
 static void SpriteCB_CameraObject(struct Sprite *);
 static void CameraObject_0(struct Sprite *);
 static void CameraObject_1(struct Sprite *);
 static void CameraObject_2(struct Sprite *);
-static struct ObjectEventTemplate *FindObjectEventTemplateByLocalId(u8 localId, struct ObjectEventTemplate *templates, u8 count);
+static struct ObjectEventTemplate *FindObjectEventTemplateByLocalId(u8, struct ObjectEventTemplate *, u8);
 static void ClearObjectEventMovement(struct ObjectEvent *, struct Sprite *);
 static void ObjectEventSetSingleMovement(struct ObjectEvent *, struct Sprite *, u8);
 static void SetSpriteDataForNormalStep(struct Sprite *, u8, u8);
-static void InitSpriteForFigure8Anim(struct Sprite *sprite);
-static bool8 AnimateSpriteInFigure8(struct Sprite *sprite);
+static void InitSpriteForFigure8Anim(struct Sprite *);
+static bool8 AnimateSpriteInFigure8(struct Sprite *);
 static void SpriteCB_VirtualObject(struct Sprite *);
 static void DoShadowFieldEffect(struct ObjectEvent *);
 static void SetJumpSpriteData(struct Sprite *, u8, u8, u8);
-static void SetWalkSlowSpriteData(struct Sprite *sprite, u8 direction);
-static bool8 UpdateWalkSlowAnim(struct Sprite *sprite);
-static u8 DoJumpSpriteMovement(struct Sprite *sprite);
-static u8 DoJumpSpecialSpriteMovement(struct Sprite *sprite);
+static void SetWalkSlowSpriteData(struct Sprite *, u8);
+static bool8 UpdateWalkSlowAnim(struct Sprite *);
+static u8 DoJumpSpriteMovement(struct Sprite *);
+static u8 DoJumpSpecialSpriteMovement(struct Sprite *);
 static void CreateLevitateMovementTask(struct ObjectEvent *);
 static void DestroyLevitateMovementTask(u8);
-static bool8 NpcTakeStep(struct Sprite *sprite);
+static bool8 NpcTakeStep(struct Sprite *);
+static bool8 IsElevationMismatchAt(u8, s16, s16);
+static bool8 AreElevationsCompatible(u8 a, u8 b);
 
 static const struct SpriteFrameImage sPicTable_PechaBerryTree[];
 
@@ -1433,7 +1435,7 @@ static u8 TrySetupObjectEventSprite(struct ObjectEventTemplate *objectEventTempl
     if (!objectEvent->inanimate)
         StartSpriteAnim(sprite, GetFaceDirectionAnimNum(objectEvent->facingDirection));
 
-    SetObjectSubpriorityByZCoord(objectEvent->previousElevation, sprite, 1);
+    SetObjectSubpriorityByElevation(objectEvent->previousElevation, sprite, 1);
     UpdateObjectEventVisibility(objectEvent, sprite);
     return objectEventId;
 }
@@ -1470,7 +1472,7 @@ u8 SpawnSpecialObjectEvent(struct ObjectEventTemplate *objectEventTemplate)
     return TrySpawnObjectEventTemplate(objectEventTemplate, gSaveBlock1Ptr->location.mapNum, gSaveBlock1Ptr->location.mapGroup, cameraX, cameraY);
 }
 
-u8 SpawnSpecialObjectEventParameterized(u8 graphicsId, u8 movementBehavior, u8 localId, s16 x, s16 y, u8 z)
+u8 SpawnSpecialObjectEventParameterized(u8 graphicsId, u8 movementBehavior, u8 localId, s16 x, s16 y, u8 elevation)
 {
     struct ObjectEventTemplate objectEventTemplate;
 
@@ -1481,7 +1483,7 @@ u8 SpawnSpecialObjectEventParameterized(u8 graphicsId, u8 movementBehavior, u8 l
     objectEventTemplate.inConnection = 0;
     objectEventTemplate.x = x;
     objectEventTemplate.y = y;
-    objectEventTemplate.elevation = z;
+    objectEventTemplate.elevation = elevation;
     objectEventTemplate.movementType = movementBehavior;
     objectEventTemplate.movementRangeX = 0;
     objectEventTemplate.movementRangeY = 0;
@@ -1560,7 +1562,7 @@ u8 CreateObjectGraphicsSprite(u16 graphicsId, void (*callback)(struct Sprite *),
 // A unique id is given as an argument and stored in the sprite data to allow referring back to the same virtual object.
 // They can be turned (and, in the case of the Union Room, animated teleporting in and out) but do not have movement types
 // or any of the other data normally associated with object events.
-u8 CreateVirtualObject(u8 graphicsId, u8 virtualObjId, s16 x, s16 y, u8 z, u8 direction)
+u8 CreateVirtualObject(u8 graphicsId, u8 virtualObjId, s16 x, s16 y, u8 elevation, u8 direction)
 {
     u8 spriteId;
     struct Sprite *sprite;
@@ -1587,7 +1589,7 @@ u8 CreateVirtualObject(u8 graphicsId, u8 virtualObjId, s16 x, s16 y, u8 z, u8 di
 
         sprite->coordOffsetEnabled = TRUE;
         sprite->sVirtualObjId = virtualObjId;
-        sprite->sVirtualObjElev = z;
+        sprite->sVirtualObjElev = elevation;
         if (graphicsInfo->paletteSlot == 10)
             LoadSpecialObjectReflectionPalette(graphicsInfo->paletteTag, graphicsInfo->paletteSlot);
         else if (graphicsInfo->paletteSlot >= 16)
@@ -1598,8 +1600,8 @@ u8 CreateVirtualObject(u8 graphicsId, u8 virtualObjId, s16 x, s16 y, u8 z, u8 di
             SetSubspriteTables(sprite, subspriteTables);
             sprite->subspriteMode = SUBSPRITES_IGNORE_PRIORITY;
         }
-        InitObjectPriorityByZCoord(sprite, z);
-        SetObjectSubpriorityByZCoord(z, sprite, 1);
+        InitObjectPriorityByElevation(sprite, elevation);
+        SetObjectSubpriorityByElevation(elevation, sprite, 1);
         StartSpriteAnim(sprite, GetFaceDirectionAnimNum(direction));
     }
     return spriteId;
@@ -1755,7 +1757,7 @@ static void SpawnObjectEventOnReturnToField(u8 objectEventId, s16 x, s16 y)
             StartSpriteAnim(sprite, GetFaceDirectionAnimNum(objectEvent->facingDirection));
 
         ResetObjectEventFldEffData(objectEvent);
-        SetObjectSubpriorityByZCoord(objectEvent->previousElevation, sprite, 1);
+        SetObjectSubpriorityByElevation(objectEvent->previousElevation, sprite, 1);
     }
 }
 
@@ -2148,7 +2150,7 @@ void UpdateObjectEventCoordsForCameraUpdate(void)
     }
 }
 
-u8 GetObjectEventIdByXYZ(u16 x, u16 y, u8 z)
+u8 GetObjectEventIdByPosition(u16 x, u16 y, u8 elevation)
 {
     u8 i;
 
@@ -2156,16 +2158,18 @@ u8 GetObjectEventIdByXYZ(u16 x, u16 y, u8 z)
     {
         if (gObjectEvents[i].active)
         {
-            if (gObjectEvents[i].currentCoords.x == x && gObjectEvents[i].currentCoords.y == y && ObjectEventDoesZCoordMatch(&gObjectEvents[i], z))
+            if (gObjectEvents[i].currentCoords.x == x
+             && gObjectEvents[i].currentCoords.y == y
+             && ObjectEventDoesElevationMatch(&gObjectEvents[i], elevation))
                 return i;
         }
     }
     return OBJECT_EVENTS_COUNT;
 }
 
-static bool8 ObjectEventDoesZCoordMatch(struct ObjectEvent *objectEvent, u8 z)
+static bool8 ObjectEventDoesElevationMatch(struct ObjectEvent *objectEvent, u8 elevation)
 {
-    if (objectEvent->currentElevation != 0 && z != 0 && objectEvent->currentElevation != z)
+    if (objectEvent->currentElevation != 0 && elevation != 0 && objectEvent->currentElevation != elevation)
         return FALSE;
 
     return TRUE;
@@ -4630,7 +4634,7 @@ u8 GetCollisionAtCoords(struct ObjectEvent *objectEvent, s16 x, s16 y, u32 dir)
         return COLLISION_IMPASSABLE;
     else if (objectEvent->trackedByCamera && !CanCameraMoveInDirection(direction))
         return COLLISION_IMPASSABLE;
-    else if (IsZCoordMismatchAt(objectEvent->currentElevation, x, y))
+    else if (IsElevationMismatchAt(objectEvent->currentElevation, x, y))
         return COLLISION_ELEVATION_MISMATCH;
     else if (DoesObjectCollideWithObjectAt(objectEvent, x, y))
         return COLLISION_OBJECT_EVENT;
@@ -4645,7 +4649,7 @@ u8 GetCollisionFlagsAtCoords(struct ObjectEvent *objectEvent, s16 x, s16 y, u8 d
         flags |= 1;
     if (MapGridIsImpassableAt(x, y) || GetMapBorderIdAt(x, y) == -1 || IsMetatileDirectionallyImpassable(objectEvent, x, y, direction) || (objectEvent->trackedByCamera && !CanCameraMoveInDirection(direction)))
         flags |= 2;
-    if (IsZCoordMismatchAt(objectEvent->currentElevation, x, y))
+    if (IsElevationMismatchAt(objectEvent->currentElevation, x, y))
         flags |= 4;
     if (DoesObjectCollideWithObjectAt(objectEvent, x, y))
         flags |= 8;
@@ -4699,7 +4703,7 @@ static bool8 DoesObjectCollideWithObjectAt(struct ObjectEvent *objectEvent, s16
         {
             if ((curObject->currentCoords.x == x && curObject->currentCoords.y == y) || (curObject->previousCoords.x == x && curObject->previousCoords.y == y))
             {
-                if (AreZCoordsCompatible(objectEvent->currentElevation, curObject->currentElevation))
+                if (AreElevationsCompatible(objectEvent->currentElevation, curObject->currentElevation))
                     return TRUE;
             }
         }
@@ -7667,23 +7671,23 @@ static void SetObjectEventSpriteOamTableForLongGrass(struct ObjectEvent *objEven
 
     sprite->subspriteTableNum = 4;
 
-    if (ZCoordToPriority(objEvent->previousElevation) == 1)
+    if (ElevationToPriority(objEvent->previousElevation) == 1)
         sprite->subspriteTableNum = 5;
 }
 
-bool8 IsZCoordMismatchAt(u8 z, s16 x, s16 y)
+static bool8 IsElevationMismatchAt(u8 elevation, s16 x, s16 y)
 {
-    u8 mapZ;
+    u8 mapElevation;
 
-    if (z == 0)
+    if (elevation == 0)
         return FALSE;
 
-    mapZ = MapGridGetZCoordAt(x, y);
+    mapElevation = MapGridGetElevationAt(x, y);
 
-    if (mapZ == 0 || mapZ == 15)
+    if (mapElevation == 0 || mapElevation == 15)
         return FALSE;
 
-    if (mapZ != z)
+    if (mapElevation != elevation)
         return TRUE;
 
     return FALSE;
@@ -7701,43 +7705,43 @@ static const u8 sElevationToSubspriteTableNum[] = {
     1, 1, 1, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 0, 0, 1,
 };
 
-void UpdateObjectEventZCoordAndPriority(struct ObjectEvent *objEvent, struct Sprite *sprite)
+static void UpdateObjectEventElevationAndPriority(struct ObjectEvent *objEvent, struct Sprite *sprite)
 {
     if (objEvent->fixedPriority)
         return;
 
-    ObjectEventUpdateZCoord(objEvent);
+    ObjectEventUpdateElevation(objEvent);
 
     sprite->subspriteTableNum = sElevationToSubspriteTableNum[objEvent->previousElevation];
     sprite->oam.priority = sElevationToPriority[objEvent->previousElevation];
 }
 
-static void InitObjectPriorityByZCoord(struct Sprite *sprite, u8 z)
+static void InitObjectPriorityByElevation(struct Sprite *sprite, u8 elevation)
 {
-    sprite->subspriteTableNum = sElevationToSubspriteTableNum[z];
-    sprite->oam.priority = sElevationToPriority[z];
+    sprite->subspriteTableNum = sElevationToSubspriteTableNum[elevation];
+    sprite->oam.priority = sElevationToPriority[elevation];
 }
 
-u8 ZCoordToPriority(u8 z)
+u8 ElevationToPriority(u8 elevation)
 {
-    return sElevationToPriority[z];
+    return sElevationToPriority[elevation];
 }
 
-void ObjectEventUpdateZCoord(struct ObjectEvent *objEvent)
+void ObjectEventUpdateElevation(struct ObjectEvent *objEvent)
 {
-    u8 z = MapGridGetZCoordAt(objEvent->currentCoords.x, objEvent->currentCoords.y);
-    u8 z2 = MapGridGetZCoordAt(objEvent->previousCoords.x, objEvent->previousCoords.y);
+    u8 curElevation = MapGridGetElevationAt(objEvent->currentCoords.x, objEvent->currentCoords.y);
+    u8 prevElevation = MapGridGetElevationAt(objEvent->previousCoords.x, objEvent->previousCoords.y);
 
-    if (z == 0xF || z2 == 0xF)
+    if (curElevation == 15 || prevElevation == 15)
         return;
 
-    objEvent->currentElevation = z;
+    objEvent->currentElevation = curElevation;
 
-    if (z != 0 && z != 0xF)
-        objEvent->previousElevation = z;
+    if (curElevation != 0 && curElevation != 15)
+        objEvent->previousElevation = curElevation;
 }
 
-void SetObjectSubpriorityByZCoord(u8 elevation, struct Sprite *sprite, u8 subpriority)
+void SetObjectSubpriorityByElevation(u8 elevation, struct Sprite *sprite, u8 subpriority)
 {
     s32 tmp = sprite->centerToCornerVecY;
     u32 tmpa = *(u16 *)&sprite->y;
@@ -7752,10 +7756,10 @@ static void ObjectEventUpdateSubpriority(struct ObjectEvent *objEvent, struct Sp
     if (objEvent->fixedPriority)
         return;
 
-    SetObjectSubpriorityByZCoord(objEvent->previousElevation, sprite, 1);
+    SetObjectSubpriorityByElevation(objEvent->previousElevation, sprite, 1);
 }
 
-bool8 AreZCoordsCompatible(u8 a, u8 b)
+static bool8 AreElevationsCompatible(u8 a, u8 b)
 {
     if (a == 0 || b == 0)
         return TRUE;
@@ -8051,7 +8055,7 @@ static void DoGroundEffects_OnSpawn(struct ObjectEvent *objEvent, struct Sprite
     if (objEvent->triggerGroundEffectsOnMove)
     {
         flags = 0;
-        UpdateObjectEventZCoordAndPriority(objEvent, sprite);
+        UpdateObjectEventElevationAndPriority(objEvent, sprite);
         GetAllGroundEffectFlags_OnSpawn(objEvent, &flags);
         SetObjectEventSpriteOamTableForLongGrass(objEvent, sprite);
         DoFlaggedGroundEffects(objEvent, sprite, flags);
@@ -8067,7 +8071,7 @@ static void DoGroundEffects_OnBeginStep(struct ObjectEvent *objEvent, struct Spr
     if (objEvent->triggerGroundEffectsOnMove)
     {
         flags = 0;
-        UpdateObjectEventZCoordAndPriority(objEvent, sprite);
+        UpdateObjectEventElevationAndPriority(objEvent, sprite);
         GetAllGroundEffectFlags_OnBeginStep(objEvent, &flags);
         SetObjectEventSpriteOamTableForLongGrass(objEvent, sprite);
         filters_out_some_ground_effects(objEvent, &flags);
@@ -8084,7 +8088,7 @@ static void DoGroundEffects_OnFinishStep(struct ObjectEvent *objEvent, struct Sp
     if (objEvent->triggerGroundEffectsOnStop)
     {
         flags = 0;
-        UpdateObjectEventZCoordAndPriority(objEvent, sprite);
+        UpdateObjectEventElevationAndPriority(objEvent, sprite);
         GetAllGroundEffectFlags_OnFinishStep(objEvent, &flags);
         SetObjectEventSpriteOamTableForLongGrass(objEvent, sprite);
         FilterOutStepOnPuddleGroundEffectIfJumping(objEvent, &flags);
@@ -8548,7 +8552,7 @@ void UpdateObjectEventSpriteInvisibility(struct Sprite *sprite, bool8 invisible)
 static void SpriteCB_VirtualObject(struct Sprite *sprite)
 {
     VirtualObject_UpdateAnim(sprite);
-    SetObjectSubpriorityByZCoord(sprite->sVirtualObjElev, sprite, 1);
+    SetObjectSubpriorityByElevation(sprite->sVirtualObjElev, sprite, 1);
     UpdateObjectEventSpriteInvisibility(sprite, sprite->sInvisible);
 }
 
diff --git a/src/field_camera.c b/src/field_camera.c
index a36b6883c..0a00dcbee 100644
--- a/src/field_camera.c
+++ b/src/field_camera.c
@@ -14,7 +14,6 @@
 
 EWRAM_DATA bool8 gUnusedBikeCameraAheadPanback = FALSE;
 
-// Static type declarations
 struct FieldCameraOffset
 {
     u8 xPixelOffset;
@@ -24,18 +23,16 @@ struct FieldCameraOffset
     bool8 copyBGToVRAM;
 };
 
-// static functions
-static void RedrawMapSliceNorth(struct FieldCameraOffset *cameraOffset, const struct MapLayout *mapLayout);
-static void RedrawMapSliceSouth(struct FieldCameraOffset *cameraOffset, const struct MapLayout *mapLayout);
-static void RedrawMapSliceEast(struct FieldCameraOffset *cameraOffset, const struct MapLayout *mapLayout);
-static void RedrawMapSliceWest(struct FieldCameraOffset *cameraOffset, const struct MapLayout *mapLayout);
-static s32 MapPosToBgTilemapOffset(struct FieldCameraOffset *a, s32 x, s32 y);
-static void DrawWholeMapViewInternal(int x, int y, const struct MapLayout *mapLayout);
-static void DrawMetatileAt(const struct MapLayout *mapLayout, u16, int, int);
-static void DrawMetatile(s32 a, u16 *b, u16 c);
+static void RedrawMapSliceNorth(struct FieldCameraOffset *, const struct MapLayout *);
+static void RedrawMapSliceSouth(struct FieldCameraOffset *, const struct MapLayout *);
+static void RedrawMapSliceEast(struct FieldCameraOffset *, const struct MapLayout *);
+static void RedrawMapSliceWest(struct FieldCameraOffset *, const struct MapLayout *);
+static s32 MapPosToBgTilemapOffset(struct FieldCameraOffset *, s32, s32);
+static void DrawWholeMapViewInternal(int, int, const struct MapLayout *);
+static void DrawMetatileAt(const struct MapLayout *, u16, int, int);
+static void DrawMetatile(s32, u16 *, u16);
 static void CameraPanningCB_PanAhead(void);
 
-// IWRAM bss vars
 static struct FieldCameraOffset sFieldCameraOffset;
 static s16 sHorizontalCameraPan;
 static s16 sVerticalCameraPan;
@@ -46,7 +43,6 @@ struct CameraObject gFieldCamera;
 u16 gTotalCameraPixelOffsetY;
 u16 gTotalCameraPixelOffsetX;
 
-// text
 static void ResetCameraOffset(struct FieldCameraOffset *cameraOffset)
 {
     cameraOffset->xTileOffset = 0;
@@ -222,7 +218,7 @@ void DrawDoorMetatileAt(int x, int y, u16 *arr)
 
     if (offset >= 0)
     {
-        DrawMetatile(1, arr, offset);
+        DrawMetatile(METATILE_LAYER_TYPE_COVERED, arr, offset);
         sFieldCameraOffset.copyBGToVRAM = TRUE;
     }
 }
@@ -244,66 +240,66 @@ static void DrawMetatileAt(const struct MapLayout *mapLayout, u16 offset, int x,
     DrawMetatile(MapGridGetMetatileLayerTypeAt(x, y), metatiles + metatileId * 8, offset);
 }
 
-static void DrawMetatile(s32 metatileLayerType, u16 *metatiles, u16 offset)
+static void DrawMetatile(s32 metatileLayerType, u16 *tiles, u16 offset)
 {
     switch (metatileLayerType)
     {
-    case 2: // LAYER_TYPE_
+    case METATILE_LAYER_TYPE_SPLIT:
         // Draw metatile's bottom layer to the bottom background layer.
-        gBGTilemapBuffers3[offset] = metatiles[0];
-        gBGTilemapBuffers3[offset + 1] = metatiles[1];
-        gBGTilemapBuffers3[offset + 0x20] = metatiles[2];
-        gBGTilemapBuffers3[offset + 0x21] = metatiles[3];
+        gOverworldTilemapBuffer_Bg3[offset] = tiles[0];
+        gOverworldTilemapBuffer_Bg3[offset + 1] = tiles[1];
+        gOverworldTilemapBuffer_Bg3[offset + 0x20] = tiles[2];
+        gOverworldTilemapBuffer_Bg3[offset + 0x21] = tiles[3];
 
         // Draw transparent tiles to the middle background layer.
-        gBGTilemapBuffers1[offset] = 0;
-        gBGTilemapBuffers1[offset + 1] = 0;
-        gBGTilemapBuffers1[offset + 0x20] = 0;
-        gBGTilemapBuffers1[offset + 0x21] = 0;
+        gOverworldTilemapBuffer_Bg2[offset] = 0;
+        gOverworldTilemapBuffer_Bg2[offset + 1] = 0;
+        gOverworldTilemapBuffer_Bg2[offset + 0x20] = 0;
+        gOverworldTilemapBuffer_Bg2[offset + 0x21] = 0;
 
         // Draw metatile's top layer to the top background layer.
-        gBGTilemapBuffers2[offset] = metatiles[4];
-        gBGTilemapBuffers2[offset + 1] = metatiles[5];
-        gBGTilemapBuffers2[offset + 0x20] = metatiles[6];
-        gBGTilemapBuffers2[offset + 0x21] = metatiles[7];
+        gOverworldTilemapBuffer_Bg1[offset] = tiles[4];
+        gOverworldTilemapBuffer_Bg1[offset + 1] = tiles[5];
+        gOverworldTilemapBuffer_Bg1[offset + 0x20] = tiles[6];
+        gOverworldTilemapBuffer_Bg1[offset + 0x21] = tiles[7];
         break;
-    case 1:  // LAYER_TYPE_COVERED_BY_OBJECTS
+    case METATILE_LAYER_TYPE_COVERED:
         // Draw metatile's bottom layer to the bottom background layer.
-        gBGTilemapBuffers3[offset] = metatiles[0];
-        gBGTilemapBuffers3[offset + 1] = metatiles[1];
-        gBGTilemapBuffers3[offset + 0x20] = metatiles[2];
-        gBGTilemapBuffers3[offset + 0x21] = metatiles[3];
+        gOverworldTilemapBuffer_Bg3[offset] = tiles[0];
+        gOverworldTilemapBuffer_Bg3[offset + 1] = tiles[1];
+        gOverworldTilemapBuffer_Bg3[offset + 0x20] = tiles[2];
+        gOverworldTilemapBuffer_Bg3[offset + 0x21] = tiles[3];
 
         // Draw metatile's top layer to the middle background layer.
-        gBGTilemapBuffers1[offset] = metatiles[4];
-        gBGTilemapBuffers1[offset + 1] = metatiles[5];
-        gBGTilemapBuffers1[offset + 0x20] = metatiles[6];
-        gBGTilemapBuffers1[offset + 0x21] = metatiles[7];
+        gOverworldTilemapBuffer_Bg2[offset] = tiles[4];
+        gOverworldTilemapBuffer_Bg2[offset + 1] = tiles[5];
+        gOverworldTilemapBuffer_Bg2[offset + 0x20] = tiles[6];
+        gOverworldTilemapBuffer_Bg2[offset + 0x21] = tiles[7];
 
         // Draw transparent tiles to the top background layer.
-        gBGTilemapBuffers2[offset] = 0;
-        gBGTilemapBuffers2[offset + 1] = 0;
-        gBGTilemapBuffers2[offset + 0x20] = 0;
-        gBGTilemapBuffers2[offset + 0x21] = 0;
+        gOverworldTilemapBuffer_Bg1[offset] = 0;
+        gOverworldTilemapBuffer_Bg1[offset + 1] = 0;
+        gOverworldTilemapBuffer_Bg1[offset + 0x20] = 0;
+        gOverworldTilemapBuffer_Bg1[offset + 0x21] = 0;
         break;
-    case 0: // LAYER_TYPE_NORMAL
+    case METATILE_LAYER_TYPE_NORMAL:
         // Draw garbage to the bottom background layer.
-        gBGTilemapBuffers3[offset] = 0x3014;
-        gBGTilemapBuffers3[offset + 1] = 0x3014;
-        gBGTilemapBuffers3[offset + 0x20] = 0x3014;
-        gBGTilemapBuffers3[offset + 0x21] = 0x3014;
+        gOverworldTilemapBuffer_Bg3[offset] = 0x3014;
+        gOverworldTilemapBuffer_Bg3[offset + 1] = 0x3014;
+        gOverworldTilemapBuffer_Bg3[offset + 0x20] = 0x3014;
+        gOverworldTilemapBuffer_Bg3[offset + 0x21] = 0x3014;
 
         // Draw metatile's bottom layer to the middle background layer.
-        gBGTilemapBuffers1[offset] = metatiles[0];
-        gBGTilemapBuffers1[offset + 1] = metatiles[1];
-        gBGTilemapBuffers1[offset + 0x20] = metatiles[2];
-        gBGTilemapBuffers1[offset + 0x21] = metatiles[3];
+        gOverworldTilemapBuffer_Bg2[offset] = tiles[0];
+        gOverworldTilemapBuffer_Bg2[offset + 1] = tiles[1];
+        gOverworldTilemapBuffer_Bg2[offset + 0x20] = tiles[2];
+        gOverworldTilemapBuffer_Bg2[offset + 0x21] = tiles[3];
 
         // Draw metatile's top layer to the top background layer, which covers object event sprites.
-        gBGTilemapBuffers2[offset] = metatiles[4];
-        gBGTilemapBuffers2[offset + 1] = metatiles[5];
-        gBGTilemapBuffers2[offset + 0x20] = metatiles[6];
-        gBGTilemapBuffers2[offset + 0x21] = metatiles[7];
+        gOverworldTilemapBuffer_Bg1[offset] = tiles[4];
+        gOverworldTilemapBuffer_Bg1[offset + 1] = tiles[5];
+        gOverworldTilemapBuffer_Bg1[offset + 0x20] = tiles[6];
+        gOverworldTilemapBuffer_Bg1[offset + 0x21] = tiles[7];
         break;
     }
     ScheduleBgCopyTilemapToVram(1);
diff --git a/src/field_control_avatar.c b/src/field_control_avatar.c
index b5fcfdadf..cdb0db6d1 100644
--- a/src/field_control_avatar.c
+++ b/src/field_control_avatar.c
@@ -194,7 +194,7 @@ int ProcessPlayerFieldInput(struct FieldInput *input)
 static void GetPlayerPosition(struct MapPosition *position)
 {
     PlayerGetDestCoords(&position->x, &position->y);
-    position->height = PlayerGetZCoord();
+    position->elevation = PlayerGetElevation();
 }
 
 static void GetInFrontOfPlayerPosition(struct MapPosition *position)
@@ -203,10 +203,10 @@ static void GetInFrontOfPlayerPosition(struct MapPosition *position)
 
     GetXYCoordsOneStepInFrontOfPlayer(&position->x, &position->y);
     PlayerGetDestCoords(&x, &y);
-    if (MapGridGetZCoordAt(x, y) != 0)
-        position->height = PlayerGetZCoord();
+    if (MapGridGetElevationAt(x, y) != 0)
+        position->elevation = PlayerGetElevation();
     else
-        position->height = 0;
+        position->elevation = 0;
 }
 
 static u16 GetPlayerCurMetatileBehavior(int runningState)
@@ -264,9 +264,9 @@ const u8 *GetInteractedLinkPlayerScript(struct MapPosition *position, u8 metatil
     s32 i;
 
     if (!MetatileBehavior_IsCounter(MapGridGetMetatileBehaviorAt(position->x, position->y)))
-        objectEventId = GetObjectEventIdByXYZ(position->x, position->y, position->height);
+        objectEventId = GetObjectEventIdByPosition(position->x, position->y, position->elevation);
     else
-        objectEventId = GetObjectEventIdByXYZ(position->x + gDirectionToVectors[direction].x, position->y + gDirectionToVectors[direction].y, position->height);
+        objectEventId = GetObjectEventIdByPosition(position->x + gDirectionToVectors[direction].x, position->y + gDirectionToVectors[direction].y, position->elevation);
 
     if (objectEventId == OBJECT_EVENTS_COUNT || gObjectEvents[objectEventId].localId == OBJ_EVENT_ID_PLAYER)
         return NULL;
@@ -288,14 +288,14 @@ static const u8 *GetInteractedObjectEventScript(struct MapPosition *position, u8
     u8 objectEventId;
     const u8 *script;
 
-    objectEventId = GetObjectEventIdByXYZ(position->x, position->y, position->height);
+    objectEventId = GetObjectEventIdByPosition(position->x, position->y, position->elevation);
     if (objectEventId == OBJECT_EVENTS_COUNT || gObjectEvents[objectEventId].localId == OBJ_EVENT_ID_PLAYER)
     {
         if (MetatileBehavior_IsCounter(metatileBehavior) != TRUE)
             return NULL;
 
         // Look for an object event on the other side of the counter.
-        objectEventId = GetObjectEventIdByXYZ(position->x + gDirectionToVectors[direction].x, position->y + gDirectionToVectors[direction].y, position->height);
+        objectEventId = GetObjectEventIdByPosition(position->x + gDirectionToVectors[direction].x, position->y + gDirectionToVectors[direction].y, position->elevation);
         if (objectEventId == OBJECT_EVENTS_COUNT || gObjectEvents[objectEventId].localId == OBJ_EVENT_ID_PLAYER)
             return NULL;
     }
@@ -315,7 +315,7 @@ static const u8 *GetInteractedObjectEventScript(struct MapPosition *position, u8
 
 static const u8 *GetInteractedBackgroundEventScript(struct MapPosition *position, u8 metatileBehavior, u8 direction)
 {
-    struct BgEvent *bgEvent = GetBackgroundEventAtPosition(&gMapHeader, position->x - MAP_OFFSET, position->y - MAP_OFFSET, position->height);
+    struct BgEvent *bgEvent = GetBackgroundEventAtPosition(&gMapHeader, position->x - MAP_OFFSET, position->y - MAP_OFFSET, position->elevation);
 
     if (bgEvent == NULL)
         return NULL;
@@ -366,7 +366,7 @@ static const u8 *GetInteractedBackgroundEventScript(struct MapPosition *position
 
 static const u8 *GetInteractedMetatileScript(struct MapPosition *position, u8 metatileBehavior, u8 direction)
 {
-    s8 height;
+    s8 elevation;
 
     if (MetatileBehavior_IsPlayerFacingTVScreen(metatileBehavior, direction) == TRUE)
         return EventScript_TV;
@@ -409,8 +409,8 @@ static const u8 *GetInteractedMetatileScript(struct MapPosition *position, u8 me
     if (MetatileBehavior_IsTrainerHillTimer(metatileBehavior) == TRUE)
         return EventScript_TrainerHillTimer;
 
-    height = position->height;
-    if (height == MapGridGetZCoordAt(position->x, position->y))
+    elevation = position->elevation;
+    if (elevation == MapGridGetElevationAt(position->x, position->y))
     {
         if (MetatileBehavior_IsSecretBasePC(metatileBehavior) == TRUE)
             return SecretBase_EventScript_PC;
@@ -497,7 +497,7 @@ static bool8 TryStartStepBasedScript(struct MapPosition *position, u16 metatileB
 
 static bool8 TryStartCoordEventScript(struct MapPosition *position)
 {
-    u8 *script = GetCoordEventScriptAtPosition(&gMapHeader, position->x - MAP_OFFSET, position->y - MAP_OFFSET, position->height);
+    u8 *script = GetCoordEventScriptAtPosition(&gMapHeader, position->x - MAP_OFFSET, position->y - MAP_OFFSET, position->elevation);
 
     if (script == NULL)
         return FALSE;
@@ -783,7 +783,7 @@ static bool8 IsArrowWarpMetatileBehavior(u16 metatileBehavior, u8 direction)
 
 static s8 GetWarpEventAtMapPosition(struct MapHeader *mapHeader, struct MapPosition *position)
 {
-    return GetWarpEventAtPosition(mapHeader, position->x - MAP_OFFSET, position->y - MAP_OFFSET, position->height);
+    return GetWarpEventAtPosition(mapHeader, position->x - MAP_OFFSET, position->y - MAP_OFFSET, position->elevation);
 }
 
 static void SetupWarp(struct MapHeader *unused, s8 warpEventId, struct MapPosition *position)
@@ -918,7 +918,7 @@ static u8 *GetCoordEventScriptAtPosition(struct MapHeader *mapHeader, u16 x, u16
 
 u8 *GetCoordEventScriptAtMapPosition(struct MapPosition *position)
 {
-    return GetCoordEventScriptAtPosition(&gMapHeader, position->x - MAP_OFFSET, position->y - MAP_OFFSET, position->height);
+    return GetCoordEventScriptAtPosition(&gMapHeader, position->x - MAP_OFFSET, position->y - MAP_OFFSET, position->elevation);
 }
 
 static struct BgEvent *GetBackgroundEventAtPosition(struct MapHeader *mapHeader, u16 x, u16 y, u8 elevation)
diff --git a/src/field_effect_helpers.c b/src/field_effect_helpers.c
index 0acb15863..65617038d 100755
--- a/src/field_effect_helpers.c
+++ b/src/field_effect_helpers.c
@@ -359,7 +359,7 @@ void UpdateTallGrassFieldEffect(struct Sprite *sprite)
          || objectEvent->previousCoords.y != sprite->sY))
             sprite->sObjectMoved = TRUE;
 
-        // Metatile behavior var re-used
+        // Metatile behavior var re-used as subpriority
         metatileBehavior = 0;
         if (sprite->animCmdIndex == 0)
             metatileBehavior = 4;
@@ -423,7 +423,7 @@ u32 FldEff_LongGrass(void)
     {
         sprite = &gSprites[spriteId];
         sprite->coordOffsetEnabled = TRUE;
-        sprite->oam.priority = ZCoordToPriority(gFieldEffectArguments[2]);
+        sprite->oam.priority = ElevationToPriority(gFieldEffectArguments[2]);
         sprite->sElevation = gFieldEffectArguments[2];
         sprite->sX = gFieldEffectArguments[0];
         sprite->sY = gFieldEffectArguments[1];
@@ -1108,7 +1108,7 @@ void SynchroniseSurfPosition(struct ObjectEvent *playerObj, struct Sprite *sprit
         for (i = DIR_SOUTH; i <= DIR_EAST; i++, x = sprite->data[6], y = sprite->data[7])
         {
             MoveCoords(i, &x, &y);
-            if (MapGridGetZCoordAt(x, y) == 3)
+            if (MapGridGetElevationAt(x, y) == 3)
             {
                 sprite->data[5]++;
                 break;
@@ -1646,7 +1646,7 @@ void UpdateJumpImpactEffect(struct Sprite *sprite)
     else
     {
         UpdateObjectEventSpriteInvisibility(sprite, FALSE);
-        SetObjectSubpriorityByZCoord(sprite->sElevation, sprite, 0);
+        SetObjectSubpriorityByElevation(sprite->sElevation, sprite, 0);
     }
 }
 
@@ -1658,14 +1658,14 @@ void WaitFieldEffectSpriteAnim(struct Sprite *sprite)
         UpdateObjectEventSpriteInvisibility(sprite, FALSE);
 }
 
-static void UpdateGrassFieldEffectSubpriority(struct Sprite *sprite, u8 z, u8 offset)
+static void UpdateGrassFieldEffectSubpriority(struct Sprite *sprite, u8 elevation, u8 subpriority)
 {
     u8 i;
     s16 var, xhi, lyhi, yhi, ylo;
     const struct ObjectEventGraphicsInfo *graphicsInfo; // Unused Variable
     struct Sprite *linkedSprite;
 
-    SetObjectSubpriorityByZCoord(z, sprite, offset);
+    SetObjectSubpriorityByElevation(elevation, sprite, subpriority);
     for (i = 0; i < OBJECT_EVENTS_COUNT; i ++)
     {
         struct ObjectEvent *objectEvent = &gObjectEvents[i];
diff --git a/src/field_player_avatar.c b/src/field_player_avatar.c
index 150c352fc..964a62187 100644
--- a/src/field_player_avatar.c
+++ b/src/field_player_avatar.c
@@ -708,8 +708,8 @@ static u8 CheckForObjectEventStaticCollision(struct ObjectEvent *objectEvent, s1
 static bool8 CanStopSurfing(s16 x, s16 y, u8 direction)
 {
     if ((gPlayerAvatar.flags & PLAYER_AVATAR_FLAG_SURFING)
-     && MapGridGetZCoordAt(x, y) == 3
-     && GetObjectEventIdByXYZ(x, y, 3) == OBJECT_EVENTS_COUNT)
+     && MapGridGetElevationAt(x, y) == 3
+     && GetObjectEventIdByPosition(x, y, 3) == OBJECT_EVENTS_COUNT)
     {
         CreateStopSurfingTask(direction);
         return TRUE;
@@ -1168,7 +1168,7 @@ u8 GetPlayerMovementDirection(void)
     return gObjectEvents[gPlayerAvatar.objectEventId].movementDirection;
 }
 
-u8 PlayerGetZCoord(void)
+u8 PlayerGetElevation(void)
 {
     return gObjectEvents[gPlayerAvatar.objectEventId].previousElevation;
 }
@@ -1306,7 +1306,7 @@ bool8 IsPlayerFacingSurfableFishableWater(void)
 
     MoveCoords(playerObjEvent->facingDirection, &x, &y);
     if (GetCollisionAtCoords(playerObjEvent, x, y, playerObjEvent->facingDirection) == COLLISION_ELEVATION_MISMATCH
-     && PlayerGetZCoord() == 3
+     && PlayerGetElevation() == 3
      && MetatileBehavior_IsSurfableFishableWater(MapGridGetMetatileBehaviorAt(x, y)))
         return TRUE;
     else
diff --git a/src/field_specials.c b/src/field_specials.c
index 45585bcd3..f749ea8fc 100644
--- a/src/field_specials.c
+++ b/src/field_specials.c
@@ -650,10 +650,10 @@ void MauvilleGymSetDefaultBarriers(void)
                 MapGridSetMetatileIdAt(x, y, METATILE_MauvilleGym_GreenBeamH2_On);
                 break;
             case METATILE_MauvilleGym_GreenBeamH3_Off:
-                MapGridSetMetatileIdAt(x, y, METATILE_MauvilleGym_GreenBeamH3_On | METATILE_COLLISION_MASK);
+                MapGridSetMetatileIdAt(x, y, METATILE_MauvilleGym_GreenBeamH3_On | MAPGRID_COLLISION_MASK);
                 break;
             case METATILE_MauvilleGym_GreenBeamH4_Off:
-                MapGridSetMetatileIdAt(x, y, METATILE_MauvilleGym_GreenBeamH4_On | METATILE_COLLISION_MASK);
+                MapGridSetMetatileIdAt(x, y, METATILE_MauvilleGym_GreenBeamH4_On | MAPGRID_COLLISION_MASK);
                 break;
             case METATILE_MauvilleGym_RedBeamH1_On:
                 MapGridSetMetatileIdAt(x, y, METATILE_MauvilleGym_RedBeamH1_Off);
@@ -674,37 +674,37 @@ void MauvilleGymSetDefaultBarriers(void)
                 MapGridSetMetatileIdAt(x, y, METATILE_MauvilleGym_RedBeamH2_On);
                 break;
             case METATILE_MauvilleGym_RedBeamH3_Off:
-                MapGridSetMetatileIdAt(x, y, METATILE_MauvilleGym_RedBeamH3_On | METATILE_COLLISION_MASK);
+                MapGridSetMetatileIdAt(x, y, METATILE_MauvilleGym_RedBeamH3_On | MAPGRID_COLLISION_MASK);
                 break;
             case METATILE_MauvilleGym_RedBeamH4_Off:
-                MapGridSetMetatileIdAt(x, y, METATILE_MauvilleGym_RedBeamH4_On | METATILE_COLLISION_MASK);
+                MapGridSetMetatileIdAt(x, y, METATILE_MauvilleGym_RedBeamH4_On | MAPGRID_COLLISION_MASK);
                 break;
             case METATILE_MauvilleGym_GreenBeamV1_On:
-                MapGridSetMetatileIdAt(x, y, METATILE_MauvilleGym_PoleBottom_On | METATILE_COLLISION_MASK);
+                MapGridSetMetatileIdAt(x, y, METATILE_MauvilleGym_PoleBottom_On | MAPGRID_COLLISION_MASK);
                 break;
             case METATILE_MauvilleGym_GreenBeamV2_On:
                 MapGridSetMetatileIdAt(x, y, METATILE_MauvilleGym_FloorTile);
                 break;
             case METATILE_MauvilleGym_RedBeamV1_On:
-                MapGridSetMetatileIdAt(x, y, METATILE_MauvilleGym_PoleBottom_Off | METATILE_COLLISION_MASK);
+                MapGridSetMetatileIdAt(x, y, METATILE_MauvilleGym_PoleBottom_Off | MAPGRID_COLLISION_MASK);
                 break;
             case METATILE_MauvilleGym_RedBeamV2_On:
                 MapGridSetMetatileIdAt(x, y, METATILE_MauvilleGym_FloorTile);
                 break;
             case METATILE_MauvilleGym_PoleBottom_On:
-                MapGridSetMetatileIdAt(x, y, METATILE_MauvilleGym_GreenBeamV1_On | METATILE_COLLISION_MASK);
+                MapGridSetMetatileIdAt(x, y, METATILE_MauvilleGym_GreenBeamV1_On | MAPGRID_COLLISION_MASK);
                 break;
             case METATILE_MauvilleGym_FloorTile:
                 if (MapGridGetMetatileIdAt(x, y - 1) == METATILE_MauvilleGym_GreenBeamV1_On)
-                    MapGridSetMetatileIdAt(x, y, METATILE_MauvilleGym_GreenBeamV2_On | METATILE_COLLISION_MASK);
+                    MapGridSetMetatileIdAt(x, y, METATILE_MauvilleGym_GreenBeamV2_On | MAPGRID_COLLISION_MASK);
                 else
-                    MapGridSetMetatileIdAt(x, y, METATILE_MauvilleGym_RedBeamV2_On | METATILE_COLLISION_MASK);
+                    MapGridSetMetatileIdAt(x, y, METATILE_MauvilleGym_RedBeamV2_On | MAPGRID_COLLISION_MASK);
                 break;
             case METATILE_MauvilleGym_PoleBottom_Off:
-                MapGridSetMetatileIdAt(x, y, METATILE_MauvilleGym_RedBeamV1_On | METATILE_COLLISION_MASK);
+                MapGridSetMetatileIdAt(x, y, METATILE_MauvilleGym_RedBeamV1_On | MAPGRID_COLLISION_MASK);
                 break;
             case METATILE_MauvilleGym_PoleTop_Off:
-                MapGridSetMetatileIdAt(x, y, METATILE_MauvilleGym_PoleTop_On | METATILE_COLLISION_MASK);
+                MapGridSetMetatileIdAt(x, y, METATILE_MauvilleGym_PoleTop_On | MAPGRID_COLLISION_MASK);
                 break;
             case METATILE_MauvilleGym_PoleTop_On:
                 MapGridSetMetatileIdAt(x, y, METATILE_MauvilleGym_PoleTop_Off);
@@ -755,10 +755,10 @@ void MauvilleGymDeactivatePuzzle(void)
                 MapGridSetMetatileIdAt(x, y, METATILE_MauvilleGym_RedBeamH4_Off);
                 break;
             case METATILE_MauvilleGym_GreenBeamV1_On:
-                MapGridSetMetatileIdAt(x, y, METATILE_MauvilleGym_PoleBottom_On | METATILE_COLLISION_MASK);
+                MapGridSetMetatileIdAt(x, y, METATILE_MauvilleGym_PoleBottom_On | MAPGRID_COLLISION_MASK);
                 break;
             case METATILE_MauvilleGym_RedBeamV1_On:
-                MapGridSetMetatileIdAt(x, y, METATILE_MauvilleGym_PoleBottom_Off | METATILE_COLLISION_MASK);
+                MapGridSetMetatileIdAt(x, y, METATILE_MauvilleGym_PoleBottom_Off | MAPGRID_COLLISION_MASK);
                 break;
             case METATILE_MauvilleGym_GreenBeamV2_On:
             case METATILE_MauvilleGym_RedBeamV2_On:
@@ -867,8 +867,8 @@ static void PetalburgGymSetDoorMetatiles(u8 roomNumber, u16 metatileId)
     }
     for (i = 0; i < nDoors; i++)
     {
-        MapGridSetMetatileIdAt(doorCoordsX[i] + MAP_OFFSET, doorCoordsY[i] + MAP_OFFSET, metatileId | METATILE_COLLISION_MASK);
-        MapGridSetMetatileIdAt(doorCoordsX[i] + MAP_OFFSET, doorCoordsY[i] + MAP_OFFSET + 1, (metatileId + 8) | METATILE_COLLISION_MASK);
+        MapGridSetMetatileIdAt(doorCoordsX[i] + MAP_OFFSET, doorCoordsY[i] + MAP_OFFSET, metatileId | MAPGRID_COLLISION_MASK);
+        MapGridSetMetatileIdAt(doorCoordsX[i] + MAP_OFFSET, doorCoordsY[i] + MAP_OFFSET + 1, (metatileId + 8) | MAPGRID_COLLISION_MASK);
     }
     DrawWholeMapView();
 }
@@ -1040,7 +1040,7 @@ static void PCTurnOnEffect_1(s16 isPcTurnedOn, s8 dx, s8 dy)
         else if (gSpecialVar_0x8004 == PC_LOCATION_MAYS_HOUSE)
             tileId = METATILE_BrendansMaysHouse_MayPC_On;
     }
-    MapGridSetMetatileIdAt(gSaveBlock1Ptr->pos.x + dx + MAP_OFFSET, gSaveBlock1Ptr->pos.y + dy + MAP_OFFSET, tileId | METATILE_COLLISION_MASK);
+    MapGridSetMetatileIdAt(gSaveBlock1Ptr->pos.x + dx + MAP_OFFSET, gSaveBlock1Ptr->pos.y + dy + MAP_OFFSET, tileId | MAPGRID_COLLISION_MASK);
 }
 
 void DoPCTurnOffEffect(void)
@@ -1075,7 +1075,7 @@ static void PCTurnOffEffect(void)
         tileId = METATILE_BrendansMaysHouse_BrendanPC_Off;
     else if (gSpecialVar_0x8004 == 2)
         tileId = METATILE_BrendansMaysHouse_MayPC_Off;
-    MapGridSetMetatileIdAt(gSaveBlock1Ptr->pos.x + dx + MAP_OFFSET, gSaveBlock1Ptr->pos.y + dy + MAP_OFFSET, tileId | METATILE_COLLISION_MASK);
+    MapGridSetMetatileIdAt(gSaveBlock1Ptr->pos.x + dx + MAP_OFFSET, gSaveBlock1Ptr->pos.y + dy + MAP_OFFSET, tileId | MAPGRID_COLLISION_MASK);
     DrawWholeMapView();
 }
 
@@ -1106,13 +1106,13 @@ static void LotteryCornerComputerEffect(struct Task *task)
         task->data[3] = 0;
         if (task->data[4] != 0)
         {
-            MapGridSetMetatileIdAt(11 + MAP_OFFSET, 1 + MAP_OFFSET, METATILE_Shop_Laptop1_Normal | METATILE_COLLISION_MASK);
-            MapGridSetMetatileIdAt(11 + MAP_OFFSET, 2 + MAP_OFFSET, METATILE_Shop_Laptop2_Normal | METATILE_COLLISION_MASK);
+            MapGridSetMetatileIdAt(11 + MAP_OFFSET, 1 + MAP_OFFSET, METATILE_Shop_Laptop1_Normal | MAPGRID_COLLISION_MASK);
+            MapGridSetMetatileIdAt(11 + MAP_OFFSET, 2 + MAP_OFFSET, METATILE_Shop_Laptop2_Normal | MAPGRID_COLLISION_MASK);
         }
         else
         {
-            MapGridSetMetatileIdAt(11 + MAP_OFFSET, 1 + MAP_OFFSET, METATILE_Shop_Laptop1_Flash | METATILE_COLLISION_MASK);
-            MapGridSetMetatileIdAt(11 + MAP_OFFSET, 2 + MAP_OFFSET, METATILE_Shop_Laptop2_Flash | METATILE_COLLISION_MASK);
+            MapGridSetMetatileIdAt(11 + MAP_OFFSET, 1 + MAP_OFFSET, METATILE_Shop_Laptop1_Flash | MAPGRID_COLLISION_MASK);
+            MapGridSetMetatileIdAt(11 + MAP_OFFSET, 2 + MAP_OFFSET, METATILE_Shop_Laptop2_Flash | MAPGRID_COLLISION_MASK);
         }
         DrawWholeMapView();
         task->data[4] ^= 1;
@@ -1124,8 +1124,8 @@ static void LotteryCornerComputerEffect(struct Task *task)
 
 void EndLotteryCornerComputerEffect(void)
 {
-    MapGridSetMetatileIdAt(11 + MAP_OFFSET, 1 + MAP_OFFSET, METATILE_Shop_Laptop1_Normal | METATILE_COLLISION_MASK);
-    MapGridSetMetatileIdAt(11 + MAP_OFFSET, 2 + MAP_OFFSET, METATILE_Shop_Laptop2_Normal | METATILE_COLLISION_MASK);
+    MapGridSetMetatileIdAt(11 + MAP_OFFSET, 1 + MAP_OFFSET, METATILE_Shop_Laptop1_Normal | MAPGRID_COLLISION_MASK);
+    MapGridSetMetatileIdAt(11 + MAP_OFFSET, 2 + MAP_OFFSET, METATILE_Shop_Laptop2_Normal | MAPGRID_COLLISION_MASK);
     DrawWholeMapView();
 }
 
@@ -1872,7 +1872,7 @@ static void Task_MoveElevatorWindowLights(u8 taskId)
             for (y = 0; y < 3; y++)
             {
                 for (x = 0; x < 3; x++)
-                    MapGridSetMetatileIdAt(x + MAP_OFFSET + 1, y + MAP_OFFSET, sElevatorWindowTiles_Ascending[y][data[0] % 3] | METATILE_COLLISION_MASK);
+                    MapGridSetMetatileIdAt(x + MAP_OFFSET + 1, y + MAP_OFFSET, sElevatorWindowTiles_Ascending[y][data[0] % 3] | MAPGRID_COLLISION_MASK);
             }
         }
         // descending
@@ -1881,7 +1881,7 @@ static void Task_MoveElevatorWindowLights(u8 taskId)
             for (y = 0; y < 3; y++)
             {
                 for (x = 0; x < 3; x++)
-                    MapGridSetMetatileIdAt(x + MAP_OFFSET + 1, y + MAP_OFFSET, sElevatorWindowTiles_Descending[y][data[0] % 3] | METATILE_COLLISION_MASK);
+                    MapGridSetMetatileIdAt(x + MAP_OFFSET + 1, y + MAP_OFFSET, sElevatorWindowTiles_Descending[y][data[0] % 3] | MAPGRID_COLLISION_MASK);
             }
         }
         DrawWholeMapView();
diff --git a/src/field_tasks.c b/src/field_tasks.c
index 244036471..8e8875993 100644
--- a/src/field_tasks.c
+++ b/src/field_tasks.c
@@ -445,8 +445,8 @@ static void PacifidlogBridgePerStepCallback(u8 taskId)
 
 static void TryLowerFortreeBridge(s16 x, s16 y)
 {
-    u8 z = PlayerGetZCoord();
-    if (!(z & 1))
+    u8 elevation = PlayerGetElevation();
+    if (!(elevation & 1))
     {
         switch (MapGridGetMetatileIdAt(x, y))
         {
@@ -462,8 +462,8 @@ static void TryLowerFortreeBridge(s16 x, s16 y)
 
 static void TryRaiseFortreeBridge(s16 x, s16 y)
 {
-    u8 z = PlayerGetZCoord();
-    if (!(z & 1))
+    u8 elevation = PlayerGetElevation();
+    if (!(elevation & 1))
     {
         switch (MapGridGetMetatileIdAt(x, y))
         {
@@ -488,7 +488,7 @@ static void FortreeBridgePerStepCallback(u8 taskId)
 {
     bool8 isFortreeBridgeCur;
     bool8 isFortreeBridgePrev;
-    u8 z, onBridgeElevation;
+    u8 elevation, onBridgeElevation;
     s16 x, y, prevX, prevY;
     s16 *data = gTasks[taskId].data;
     PlayerGetDestCoords(&x, &y);
@@ -520,9 +520,9 @@ static void FortreeBridgePerStepCallback(u8 taskId)
         isFortreeBridgePrev = MetatileBehavior_IsFortreeBridge(MapGridGetMetatileBehaviorAt(prevX, prevY));
         
         // Make sure player isn't below bridge
-        z = PlayerGetZCoord();
+        elevation = PlayerGetElevation();
         onBridgeElevation = FALSE;
-        if ((u8)(z & 1) == 0)
+        if ((u8)(elevation & 1) == 0)
             onBridgeElevation = TRUE;
 
         if (onBridgeElevation && (isFortreeBridgeCur == TRUE || isFortreeBridgePrev == TRUE))
diff --git a/src/fieldmap.c b/src/fieldmap.c
index aff72c4c6..4dbf981cf 100644
--- a/src/fieldmap.c
+++ b/src/fieldmap.c
@@ -43,12 +43,12 @@ static void FillWestConnection(struct MapHeader const *mapHeader, struct MapHead
 static void FillEastConnection(struct MapHeader const *mapHeader, struct MapHeader const *connectedMapHeader, s32 offset);
 static void InitBackupMapLayoutConnections(struct MapHeader *mapHeader);
 static void LoadSavedMapView(void);
-static bool8 SkipCopyingMetatileFromSavedMap(u16* mapMetatilePtr, u16 mapWidth, u8 yMode);
+static bool8 SkipCopyingMetatileFromSavedMap(u16* mapBlock, u16 mapWidth, u8 yMode);
 static struct MapConnection *GetIncomingConnection(u8 direction, int x, int y);
 static bool8 IsPosInIncomingConnectingMap(u8 direction, int x, int y, struct MapConnection *connection);
 static bool8 IsCoordInIncomingConnectingMap(int coord, int srcMax, int destMax, int offset);
 
-#define MapGridGetBorderTileAt(x, y) ({                                                            \
+#define GetBorderBlockAt(x, y)({                                                                   \
     u16 block;                                                                                     \
     int i;                                                                                         \
     u16 *border = gMapHeader.mapLayout->border;                                                    \
@@ -56,12 +56,12 @@ static bool8 IsCoordInIncomingConnectingMap(int coord, int srcMax, int destMax,
     i = (x + 1) & 1;                                                                               \
     i += ((y + 1) & 1) * 2;                                                                        \
                                                                                                    \
-    block = gMapHeader.mapLayout->border[i] | METATILE_COLLISION_MASK;                             \
+    block = gMapHeader.mapLayout->border[i] | MAPGRID_COLLISION_MASK;                              \
 })
 
 #define AreCoordsWithinMapGridBounds(x, y) (x >= 0 && x < gBackupMapLayout.width && y >= 0 && y < gBackupMapLayout.height)
 
-#define MapGridGetTileAt(x, y) (AreCoordsWithinMapGridBounds(x, y) ? gBackupMapLayout.map[x + gBackupMapLayout.width * y] : MapGridGetBorderTileAt(x, y))
+#define GetMapGridBlockAt(x, y) (AreCoordsWithinMapGridBounds(x, y) ? gBackupMapLayout.map[x + gBackupMapLayout.width * y] : GetBorderBlockAt(x, y))
 
 struct MapHeader const *const GetMapHeaderFromConnection(struct MapConnection *connection)
 {
@@ -87,13 +87,13 @@ void InitMapFromSavedGame(void)
 
 void InitBattlePyramidMap(bool8 setPlayerPosition)
 {
-    CpuFastFill(METATILE_ID_UNDEFINED << 16 | METATILE_ID_UNDEFINED, gBackupMapData, sizeof(gBackupMapData));
+    CpuFastFill(MAPGRID_UNDEFINED << 16 | MAPGRID_UNDEFINED, gBackupMapData, sizeof(gBackupMapData));
     GenerateBattlePyramidFloorLayout(gBackupMapData, setPlayerPosition);
 }
 
 void InitTrainerHillMap(void)
 {
-    CpuFastFill(METATILE_ID_UNDEFINED << 16 | METATILE_ID_UNDEFINED, gBackupMapData, sizeof(gBackupMapData));
+    CpuFastFill(MAPGRID_UNDEFINED << 16 | MAPGRID_UNDEFINED, gBackupMapData, sizeof(gBackupMapData));
     GenerateTrainerHillFloorLayout(gBackupMapData);
 }
 
@@ -103,7 +103,7 @@ static void InitMapLayoutData(struct MapHeader *mapHeader)
     int width;
     int height;
     mapLayout = mapHeader->mapLayout;
-    CpuFastFill16(METATILE_ID_UNDEFINED, gBackupMapData, sizeof(gBackupMapData));
+    CpuFastFill16(MAPGRID_UNDEFINED, gBackupMapData, sizeof(gBackupMapData));
     gBackupMapLayout.map = gBackupMapData;
     width = mapLayout->width + MAP_OFFSET_W;
     gBackupMapLayout.width = width;
@@ -342,46 +342,46 @@ static void FillEastConnection(struct MapHeader const *mapHeader, struct MapHead
     }
 }
 
-u8 MapGridGetZCoordAt(int x, int y)
+u8 MapGridGetElevationAt(int x, int y)
 {
-    u16 block = MapGridGetTileAt(x, y);
+    u16 block = GetMapGridBlockAt(x, y);
 
-    if (block == METATILE_ID_UNDEFINED)
+    if (block == MAPGRID_UNDEFINED)
         return 0;
 
-    return block >> METATILE_ELEVATION_SHIFT;
+    return block >> MAPGRID_ELEVATION_SHIFT;
 }
 
 bool8 MapGridIsImpassableAt(int x, int y)
 {
-    u16 block = MapGridGetTileAt(x, y);
+    u16 block = GetMapGridBlockAt(x, y);
 
-    if (block == METATILE_ID_UNDEFINED)
+    if (block == MAPGRID_UNDEFINED)
         return TRUE;
 
-    return (block & METATILE_COLLISION_MASK) >> METATILE_COLLISION_SHIFT;
+    return (block & MAPGRID_COLLISION_MASK) >> MAPGRID_COLLISION_SHIFT;
 }
 
 u32 MapGridGetMetatileIdAt(int x, int y)
 {
-    u16 block = MapGridGetTileAt(x, y);
+    u16 block = GetMapGridBlockAt(x, y);
 
-    if (block == METATILE_ID_UNDEFINED)
-        return MapGridGetBorderTileAt(x, y) & METATILE_ID_MASK;
+    if (block == MAPGRID_UNDEFINED)
+        return GetBorderBlockAt(x, y) & MAPGRID_METATILE_ID_MASK;
 
-    return block & METATILE_ID_MASK;
+    return block & MAPGRID_METATILE_ID_MASK;
 }
 
 u32 MapGridGetMetatileBehaviorAt(int x, int y)
 {
     u16 metatile = MapGridGetMetatileIdAt(x, y);
-    return GetBehaviorByMetatileId(metatile) & METATILE_BEHAVIOR_MASK;
+    return GetMetatileAttributesById(metatile) & METATILE_ATTR_BEHAVIOR_MASK;
 }
 
 u8 MapGridGetMetatileLayerTypeAt(int x, int y)
 {
     u16 metatile = MapGridGetMetatileIdAt(x, y);
-    return (GetBehaviorByMetatileId(metatile) & METATILE_ELEVATION_MASK) >> METATILE_ELEVATION_SHIFT;
+    return (GetMetatileAttributesById(metatile) & METATILE_ATTR_LAYER_MASK) >> METATILE_ATTR_LAYER_SHIFT;
 }
 
 void MapGridSetMetatileIdAt(int x, int y, u16 metatile)
@@ -390,7 +390,7 @@ void MapGridSetMetatileIdAt(int x, int y, u16 metatile)
     if (AreCoordsWithinMapGridBounds(x, y))
     {
         i = x + y * gBackupMapLayout.width;
-        gBackupMapLayout.map[i] = (gBackupMapLayout.map[i] & METATILE_ELEVATION_MASK) | (metatile & ~METATILE_ELEVATION_MASK);
+        gBackupMapLayout.map[i] = (gBackupMapLayout.map[i] & MAPGRID_ELEVATION_MASK) | (metatile & ~MAPGRID_ELEVATION_MASK);
     }
 }
 
@@ -404,7 +404,7 @@ void MapGridSetMetatileEntryAt(int x, int y, u16 metatile)
     }
 }
 
-u16 GetBehaviorByMetatileId(u16 metatile)
+u16 GetMetatileAttributesById(u16 metatile)
 {
     u16 *attributes;
     if (metatile < NUM_METATILES_IN_PRIMARY)
@@ -565,7 +565,7 @@ static void MoveMapViewToBackup(u8 direction)
 
 int GetMapBorderIdAt(int x, int y)
 {
-    if (MapGridGetTileAt(x, y) == METATILE_ID_UNDEFINED)
+    if (GetMapGridBlockAt(x, y) == MAPGRID_UNDEFINED)
         return CONNECTION_INVALID;
 
     if (x >= (gBackupMapLayout.width - (MAP_OFFSET + 1)))
@@ -817,23 +817,23 @@ void MapGridSetMetatileImpassabilityAt(int x, int y, bool32 impassable)
     if (AreCoordsWithinMapGridBounds(x, y))
     {
         if (impassable)
-            gBackupMapLayout.map[x + gBackupMapLayout.width * y] |= METATILE_COLLISION_MASK;
+            gBackupMapLayout.map[x + gBackupMapLayout.width * y] |= MAPGRID_COLLISION_MASK;
         else
-            gBackupMapLayout.map[x + gBackupMapLayout.width * y] &= ~METATILE_COLLISION_MASK;
+            gBackupMapLayout.map[x + gBackupMapLayout.width * y] &= ~MAPGRID_COLLISION_MASK;
     }
 }
 
-static bool8 SkipCopyingMetatileFromSavedMap(u16* mapMetatilePtr, u16 mapWidth, u8 yMode)
+static bool8 SkipCopyingMetatileFromSavedMap(u16* mapBlock, u16 mapWidth, u8 yMode)
 {
     if (yMode == 0xFF)
         return FALSE;
 
     if (yMode == 0)
-        mapMetatilePtr -= mapWidth;
+        mapBlock -= mapWidth;
     else
-        mapMetatilePtr += mapWidth;
+        mapBlock += mapWidth;
 
-    if (IsLargeBreakableDecoration(*mapMetatilePtr & METATILE_ID_MASK, yMode) == TRUE)
+    if (IsLargeBreakableDecoration(*mapBlock & MAPGRID_METATILE_ID_MASK, yMode) == TRUE)
         return TRUE;
     return FALSE;
 }
diff --git a/src/fldeff_cut.c b/src/fldeff_cut.c
index daa46ad76..9129c5208 100644
--- a/src/fldeff_cut.c
+++ b/src/fldeff_cut.c
@@ -181,7 +181,7 @@ bool8 SetUpFieldMove_Cut(void)
             for (j = 0; j < CUT_NORMAL_SIDE; j++)
             {
                 x = j - 1 + gPlayerFacingPosition.x;
-                if (MapGridGetZCoordAt(x, y) == gPlayerFacingPosition.height)
+                if (MapGridGetElevationAt(x, y) == gPlayerFacingPosition.elevation)
                 {
                     tileBehavior = MapGridGetMetatileBehaviorAt(x, y);
                     if (MetatileBehavior_IsPokeGrass(tileBehavior) == TRUE
@@ -238,7 +238,7 @@ bool8 SetUpFieldMove_Cut(void)
 
                 if (tileCuttable == TRUE)
                 {
-                    if (MapGridGetZCoordAt(x, y) == gPlayerFacingPosition.height)
+                    if (MapGridGetElevationAt(x, y) == gPlayerFacingPosition.elevation)
                     {
                         u8 tileArrayId = ((sHyperCutStruct[i].y * 5) + 12) + (sHyperCutStruct[i].x);
                         tileBehavior = MapGridGetMetatileBehaviorAt(x, y);
diff --git a/src/fldeff_escalator.c b/src/fldeff_escalator.c
index 769e73562..0dc98c319 100644
--- a/src/fldeff_escalator.c
+++ b/src/fldeff_escalator.c
@@ -126,13 +126,13 @@ static void Task_DrawEscalator(u8 taskId)
             SetEscalatorMetatile(taskId, sEscalatorMetatiles_1F_1, 0);
             break;
         case 2:
-            SetEscalatorMetatile(taskId, sEscalatorMetatiles_1F_2, METATILE_COLLISION_MASK);
+            SetEscalatorMetatile(taskId, sEscalatorMetatiles_1F_2, MAPGRID_COLLISION_MASK);
             break;
         case 3:
             SetEscalatorMetatile(taskId, sEscalatorMetatiles_1F_3, 0);
             break;
         case 4:
-            SetEscalatorMetatile(taskId, sEscalatorMetatiles_2F_0, METATILE_COLLISION_MASK);
+            SetEscalatorMetatile(taskId, sEscalatorMetatiles_2F_0, MAPGRID_COLLISION_MASK);
             break;
         case 5:
             SetEscalatorMetatile(taskId, sEscalatorMetatiles_2F_1, 0);
diff --git a/src/fldeff_misc.c b/src/fldeff_misc.c
index c01babb68..4f3f53fa6 100644
--- a/src/fldeff_misc.c
+++ b/src/fldeff_misc.c
@@ -840,9 +840,9 @@ void DoSecretBasePCTurnOffEffect(void)
     PlaySE(SE_PC_OFF);
 
     if (!VarGet(VAR_CURRENT_SECRET_BASE))
-        MapGridSetMetatileIdAt(x, y, METATILE_SecretBase_PC | METATILE_COLLISION_MASK);
+        MapGridSetMetatileIdAt(x, y, METATILE_SecretBase_PC | MAPGRID_COLLISION_MASK);
     else
-        MapGridSetMetatileIdAt(x, y, METATILE_SecretBase_RegisterPC | METATILE_COLLISION_MASK);
+        MapGridSetMetatileIdAt(x, y, METATILE_SecretBase_RegisterPC | MAPGRID_COLLISION_MASK);
 
     CurrentMapDrawMetatileAt(x, y);
 }
@@ -1083,7 +1083,7 @@ static void SpriteCB_SandPillar_BreakTop(struct Sprite *sprite)
     PlaySE(SE_M_ROCK_THROW);
 
     if (MapGridGetMetatileIdAt(gFieldEffectArguments[5], gFieldEffectArguments[6] - 1) == METATILE_SecretBase_SandOrnament_TopWall)
-        MapGridSetMetatileIdAt(gFieldEffectArguments[5], gFieldEffectArguments[6] - 1, METATILE_SecretBase_Wall_TopMid | METATILE_COLLISION_MASK);
+        MapGridSetMetatileIdAt(gFieldEffectArguments[5], gFieldEffectArguments[6] - 1, METATILE_SecretBase_Wall_TopMid | MAPGRID_COLLISION_MASK);
     else
         MapGridSetMetatileIdAt(gFieldEffectArguments[5], gFieldEffectArguments[6] - 1, METATILE_SecretBase_SandOrnament_BrokenTop);
 
@@ -1103,7 +1103,7 @@ static void SpriteCB_SandPillar_BreakBase(struct Sprite *sprite)
     }
     else
     {
-        MapGridSetMetatileIdAt(gFieldEffectArguments[5], gFieldEffectArguments[6], METATILE_SecretBase_SandOrnament_BrokenBase | METATILE_COLLISION_MASK);
+        MapGridSetMetatileIdAt(gFieldEffectArguments[5], gFieldEffectArguments[6], METATILE_SecretBase_SandOrnament_BrokenBase | MAPGRID_COLLISION_MASK);
         CurrentMapDrawMetatileAt(gFieldEffectArguments[5], gFieldEffectArguments[6]);
         sprite->data[0] = 0;
         sprite->callback = SpriteCB_SandPillar_End;
diff --git a/src/fldeff_rocksmash.c b/src/fldeff_rocksmash.c
index 6f4ce8002..a30000e52 100644
--- a/src/fldeff_rocksmash.c
+++ b/src/fldeff_rocksmash.c
@@ -19,7 +19,6 @@
 #include "constants/map_types.h"
 #include "constants/songs.h"
 
-// static functions
 static void Task_DoFieldMove_Init(u8 taskId);
 static void Task_DoFieldMove_ShowMonAfterPose(u8 taskId);
 static void Task_DoFieldMove_WaitForMon(u8 taskId);
@@ -28,14 +27,13 @@ static void Task_DoFieldMove_RunFunc(u8 taskId);
 static void FieldCallback_RockSmash(void);
 static void FieldMove_RockSmash(void);
 
-// text
 bool8 CheckObjectGraphicsInFrontOfPlayer(u8 graphicsId)
 {
     u8 objEventId;
 
     GetXYCoordsOneStepInFrontOfPlayer(&gPlayerFacingPosition.x, &gPlayerFacingPosition.y);
-    gPlayerFacingPosition.height = PlayerGetZCoord();
-    objEventId = GetObjectEventIdByXYZ(gPlayerFacingPosition.x, gPlayerFacingPosition.y, gPlayerFacingPosition.height);
+    gPlayerFacingPosition.elevation = PlayerGetElevation();
+    objEventId = GetObjectEventIdByPosition(gPlayerFacingPosition.x, gPlayerFacingPosition.y, gPlayerFacingPosition.elevation);
     if (gObjectEvents[objEventId].graphicsId != graphicsId)
     {
         return FALSE;
diff --git a/src/item_use.c b/src/item_use.c
index 29ceb7cae..c9a7fe1c7 100755
--- a/src/item_use.c
+++ b/src/item_use.c
@@ -725,11 +725,11 @@ static void ItemUseOnFieldCB_WailmerPailBerry(u8 taskId)
 static bool8 TryToWaterSudowoodo(void)
 {
     u16 x, y;
-    u8 z;
+    u8 elevation;
     u8 objId;
     GetXYCoordsOneStepInFrontOfPlayer(&x, &y);
-    z = PlayerGetZCoord();
-    objId = GetObjectEventIdByXYZ(x, y, z);
+    elevation = PlayerGetElevation();
+    objId = GetObjectEventIdByPosition(x, y, elevation);
     if (objId == OBJECT_EVENTS_COUNT || gObjectEvents[objId].graphicsId != OBJ_EVENT_GFX_SUDOWOODO)
         return FALSE;
     else
diff --git a/src/metatile_behavior.c b/src/metatile_behavior.c
index 6b58e3f05..72d3ac632 100644
--- a/src/metatile_behavior.c
+++ b/src/metatile_behavior.c
@@ -2,254 +2,129 @@
 #include "metatile_behavior.h"
 #include "constants/metatile_behaviors.h"
 
-#define TILE_FLAG_ENCOUNTER_TILE 1
-#define TILE_FLAG_SURFABLE 2
-
-#define TILE_ATTRIBUTES(unused, surfable, wildEncounter) (((wildEncounter) ? 1 : 0) | ((surfable) ? 2 : 0) | ((unused) ? 4 : 0))
-
-// wonder what the third flag is supposed to do
-static const u8 sTileBitAttributes[] =
-{
-    [MB_NORMAL] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_SECRET_BASE_WALL] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_TALL_GRASS] = TILE_ATTRIBUTES(TRUE, FALSE, TRUE),
-    [MB_LONG_GRASS] = TILE_ATTRIBUTES(TRUE, FALSE, TRUE),
-    [MB_UNUSED_04] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_05] = TILE_ATTRIBUTES(FALSE, FALSE, TRUE),
-    [MB_DEEP_SAND] = TILE_ATTRIBUTES(TRUE, FALSE, TRUE),
-    [MB_SHORT_GRASS] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_UNUSED_CAVE] = TILE_ATTRIBUTES(TRUE, FALSE, TRUE),
-    [MB_LONG_GRASS_SOUTH_EDGE] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_NO_RUNNING] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_INDOOR_ENCOUNTER] = TILE_ATTRIBUTES(TRUE, FALSE, TRUE),
-    [MB_MOUNTAIN_TOP] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_BATTLE_PYRAMID_WARP] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_MOSSDEEP_GYM_WARP] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_MT_PYRE_HOLE] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_POND_WATER] = TILE_ATTRIBUTES(TRUE, TRUE, TRUE),
-    [MB_SEMI_DEEP_WATER] = TILE_ATTRIBUTES(TRUE, TRUE, TRUE),
-    [MB_DEEP_WATER] = TILE_ATTRIBUTES(TRUE, TRUE, TRUE),
-    [MB_WATERFALL] = TILE_ATTRIBUTES(TRUE, TRUE, FALSE),
-    [MB_SOOTOPOLIS_DEEP_WATER] = TILE_ATTRIBUTES(TRUE, TRUE, FALSE),
-    [MB_OCEAN_WATER] = TILE_ATTRIBUTES(TRUE, TRUE, TRUE),
-    [MB_PUDDLE] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_SHALLOW_WATER] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_UNUSED_SOOTOPOLIS_DEEP_WATER] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_NO_SURFACING] = TILE_ATTRIBUTES(TRUE, TRUE, FALSE),
-    [MB_UNUSED_SOOTOPOLIS_DEEP_WATER_2] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_STAIRS_OUTSIDE_ABANDONED_SHIP] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_SHOAL_CAVE_ENTRANCE] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_UNUSED_1D] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_1E] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_1F] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_ICE] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_SAND] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_SEAWEED] = TILE_ATTRIBUTES(TRUE, TRUE, TRUE),
-    [MB_UNUSED_23] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_ASHGRASS] = TILE_ATTRIBUTES(TRUE, FALSE, TRUE),
-    [MB_FOOTPRINTS] = TILE_ATTRIBUTES(TRUE, FALSE, TRUE),
-    [MB_THIN_ICE] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_CRACKED_ICE] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_HOT_SPRINGS] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_LAVARIDGE_GYM_B1F_WARP] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_SEAWEED_NO_SURFACING] = TILE_ATTRIBUTES(TRUE, TRUE, TRUE),
-    [MB_REFLECTION_UNDER_BRIDGE] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_UNUSED_2C] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_2D] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_2E] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_2F] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_IMPASSABLE_EAST] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_IMPASSABLE_WEST] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_IMPASSABLE_NORTH] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_IMPASSABLE_SOUTH] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_IMPASSABLE_NORTHEAST] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_IMPASSABLE_NORTHWEST] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_IMPASSABLE_SOUTHEAST] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_IMPASSABLE_SOUTHWEST] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_JUMP_EAST] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_JUMP_WEST] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_JUMP_NORTH] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_JUMP_SOUTH] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_JUMP_NORTHEAST] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_JUMP_NORTHWEST] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_JUMP_SOUTHEAST] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_JUMP_SOUTHWEST] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_WALK_EAST] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_WALK_WEST] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_WALK_NORTH] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_WALK_SOUTH] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_SLIDE_EAST] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_SLIDE_WEST] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_SLIDE_NORTH] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_SLIDE_SOUTH] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_TRICK_HOUSE_PUZZLE_8_FLOOR] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_UNUSED_49] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_UNUSED_4A] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_UNUSED_4B] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_4C] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_4D] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_4E] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_4F] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_EASTWARD_CURRENT] = TILE_ATTRIBUTES(TRUE, TRUE, FALSE),
-    [MB_WESTWARD_CURRENT] = TILE_ATTRIBUTES(TRUE, TRUE, FALSE),
-    [MB_NORTHWARD_CURRENT] = TILE_ATTRIBUTES(TRUE, TRUE, FALSE),
-    [MB_SOUTHWARD_CURRENT] = TILE_ATTRIBUTES(TRUE, TRUE, FALSE),
-    [MB_UNUSED_54] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_55] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_56] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_57] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_58] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_59] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_5A] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_5B] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_5C] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_5D] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_5E] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_5F] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_NON_ANIMATED_DOOR] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_LADDER] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_EAST_ARROW_WARP] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_WEST_ARROW_WARP] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_NORTH_ARROW_WARP] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_SOUTH_ARROW_WARP] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_CRACKED_FLOOR_HOLE] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_AQUA_HIDEOUT_WARP] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_LAVARIDGE_GYM_1F_WARP] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_ANIMATED_DOOR] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_UP_ESCALATOR] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_DOWN_ESCALATOR] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_WATER_DOOR] = TILE_ATTRIBUTES(TRUE, TRUE, FALSE),
-    [MB_WATER_SOUTH_ARROW_WARP] = TILE_ATTRIBUTES(TRUE, TRUE, FALSE),
-    [MB_DEEP_SOUTH_WARP] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_UNUSED_6F] = TILE_ATTRIBUTES(TRUE, TRUE, FALSE),
-    [MB_BRIDGE_OVER_OCEAN] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_BRIDGE_OVER_POND_LOW] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_BRIDGE_OVER_POND_MED] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_BRIDGE_OVER_POND_HIGH] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_PACIFIDLOG_VERTICAL_LOG_TOP] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_PACIFIDLOG_VERTICAL_LOG_BOTTOM] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_PACIFIDLOG_HORIZONTAL_LOG_LEFT] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_PACIFIDLOG_HORIZONTAL_LOG_RIGHT] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_FORTREE_BRIDGE] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_UNUSED_79] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_BRIDGE_OVER_POND_MED_EDGE_1] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_BRIDGE_OVER_POND_MED_EDGE_2] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_BRIDGE_OVER_POND_HIGH_EDGE_1] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_BRIDGE_OVER_POND_HIGH_EDGE_2] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_UNUSED_BRIDGE] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_BIKE_BRIDGE_OVER_BARRIER] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_COUNTER] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_81] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_82] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_PC] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_CABLE_BOX_RESULTS_1] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_REGION_MAP] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_TELEVISION] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_POKEBLOCK_FEEDER] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_88] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_SLOT_MACHINE] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_ROULETTE] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_CLOSED_SOOTOPOLIS_DOOR] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_TRICK_HOUSE_PUZZLE_DOOR] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_PETALBURG_GYM_DOOR] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_RUNNING_SHOES_INSTRUCTION] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_QUESTIONNAIRE] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_SECRET_BASE_SPOT_RED_CAVE] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_SECRET_BASE_SPOT_RED_CAVE_OPEN] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_SECRET_BASE_SPOT_BROWN_CAVE] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_SECRET_BASE_SPOT_BROWN_CAVE_OPEN] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_SECRET_BASE_SPOT_YELLOW_CAVE] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_SECRET_BASE_SPOT_YELLOW_CAVE_OPEN] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_SECRET_BASE_SPOT_TREE_LEFT] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_SECRET_BASE_SPOT_TREE_LEFT_OPEN] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_SECRET_BASE_SPOT_SHRUB] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_SECRET_BASE_SPOT_SHRUB_OPEN] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_SECRET_BASE_SPOT_BLUE_CAVE] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_SECRET_BASE_SPOT_BLUE_CAVE_OPEN] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_SECRET_BASE_SPOT_TREE_RIGHT] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_SECRET_BASE_SPOT_TREE_RIGHT_OPEN] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_9E] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_9F] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_BERRY_TREE_SOIL] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_A1] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_A2] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_A3] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_A4] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_A5] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_A6] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_A7] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_A8] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_A9] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_AA] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_AB] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_AC] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_AD] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_AE] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_AF] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_SECRET_BASE_PC] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_SECRET_BASE_REGISTER_PC] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_SECRET_BASE_UNUSED] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_BLOCK_DECORATION] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_SECRET_BASE_DECORATION] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_HOLDS_SMALL_DECORATION] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_UNUSED_B6] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_SECRET_BASE_NORTH_WALL] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_SECRET_BASE_BALLOON] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_SECRET_BASE_IMPASSABLE] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_SECRET_BASE_GLITTER_MAT] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_SECRET_BASE_JUMP_MAT] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_SECRET_BASE_SPIN_MAT] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_SECRET_BASE_SOUND_MAT] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_SECRET_BASE_BREAKABLE_DOOR] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_SECRET_BASE_SAND_ORNAMENT] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_IMPASSABLE_SOUTH_AND_NORTH] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_IMPASSABLE_WEST_AND_EAST] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_SECRET_BASE_HOLE] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_HOLDS_LARGE_DECORATION] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_SECRET_BASE_TV_SHIELD] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_PLAYER_ROOM_PC_ON] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_SECRET_BASE_DECORATION_BASE] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_SECRET_BASE_POSTER] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_C8] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_C9] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_CA] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_CB] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_CC] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_CD] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_CE] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_CF] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_MUDDY_SLOPE] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_BUMPY_SLOPE] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_CRACKED_FLOOR] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_ISOLATED_VERTICAL_RAIL] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_ISOLATED_HORIZONTAL_RAIL] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_VERTICAL_RAIL] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_HORIZONTAL_RAIL] = TILE_ATTRIBUTES(TRUE, FALSE, FALSE),
-    [MB_UNUSED_D7] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_D8] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_D9] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_DA] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_DB] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_DC] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_DD] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_DE] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_DF] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_PICTURE_BOOK_SHELF] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_BOOKSHELF] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_POKEMON_CENTER_BOOKSHELF] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_VASE] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_TRASH_CAN] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_SHOP_SHELF] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_BLUEPRINT] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_CABLE_BOX_RESULTS_2] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_WIRELESS_BOX_RESULTS] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_TRAINER_HILL_TIMER] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_SKY_PILLAR_CLOSED_DOOR] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_EB] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_EC] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_ED] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_EE] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
-    [MB_UNUSED_EF] = TILE_ATTRIBUTES(FALSE, FALSE, FALSE),
+#define TILE_FLAG_HAS_ENCOUNTERS (1 << 0)
+#define TILE_FLAG_SURFABLE       (1 << 1)
+#define TILE_FLAG_UNUSED         (1 << 2) // Roughly all of the traversable metatiles. Set but never read
+
+static const u8 sTileBitAttributes[NUM_METATILE_BEHAVIORS] =
+{
+    [MB_NORMAL]                          = TILE_FLAG_UNUSED,
+    [MB_TALL_GRASS]                      = TILE_FLAG_UNUSED | TILE_FLAG_HAS_ENCOUNTERS,
+    [MB_LONG_GRASS]                      = TILE_FLAG_UNUSED | TILE_FLAG_HAS_ENCOUNTERS,
+    [MB_UNUSED_05]                       = TILE_FLAG_HAS_ENCOUNTERS,
+    [MB_DEEP_SAND]                       = TILE_FLAG_UNUSED | TILE_FLAG_HAS_ENCOUNTERS,
+    [MB_SHORT_GRASS]                     = TILE_FLAG_UNUSED,
+    [MB_CAVE]                            = TILE_FLAG_UNUSED | TILE_FLAG_HAS_ENCOUNTERS,
+    [MB_LONG_GRASS_SOUTH_EDGE]           = TILE_FLAG_UNUSED,
+    [MB_NO_RUNNING]                      = TILE_FLAG_UNUSED,
+    [MB_INDOOR_ENCOUNTER]                = TILE_FLAG_UNUSED | TILE_FLAG_HAS_ENCOUNTERS,
+    [MB_MOUNTAIN_TOP]                    = TILE_FLAG_UNUSED,
+    [MB_BATTLE_PYRAMID_WARP]             = TILE_FLAG_UNUSED,
+    [MB_MOSSDEEP_GYM_WARP]               = TILE_FLAG_UNUSED,
+    [MB_MT_PYRE_HOLE]                    = TILE_FLAG_UNUSED,
+    [MB_POND_WATER]                      = TILE_FLAG_UNUSED | TILE_FLAG_SURFABLE | TILE_FLAG_HAS_ENCOUNTERS,
+    [MB_SEMI_DEEP_WATER]                 = TILE_FLAG_UNUSED | TILE_FLAG_SURFABLE | TILE_FLAG_HAS_ENCOUNTERS,
+    [MB_DEEP_WATER]                      = TILE_FLAG_UNUSED | TILE_FLAG_SURFABLE | TILE_FLAG_HAS_ENCOUNTERS,
+    [MB_WATERFALL]                       = TILE_FLAG_UNUSED | TILE_FLAG_SURFABLE,
+    [MB_SOOTOPOLIS_DEEP_WATER]           = TILE_FLAG_UNUSED | TILE_FLAG_SURFABLE,
+    [MB_OCEAN_WATER]                     = TILE_FLAG_UNUSED | TILE_FLAG_SURFABLE | TILE_FLAG_HAS_ENCOUNTERS,
+    [MB_PUDDLE]                          = TILE_FLAG_UNUSED,
+    [MB_SHALLOW_WATER]                   = TILE_FLAG_UNUSED,
+    [MB_NO_SURFACING]                    = TILE_FLAG_UNUSED | TILE_FLAG_SURFABLE,
+    [MB_STAIRS_OUTSIDE_ABANDONED_SHIP]   = TILE_FLAG_UNUSED,
+    [MB_SHOAL_CAVE_ENTRANCE]             = TILE_FLAG_UNUSED,
+    [MB_ICE]                             = TILE_FLAG_UNUSED,
+    [MB_SAND]                            = TILE_FLAG_UNUSED,
+    [MB_SEAWEED]                         = TILE_FLAG_UNUSED | TILE_FLAG_SURFABLE | TILE_FLAG_HAS_ENCOUNTERS,
+    [MB_UNUSED_23]                       = TILE_FLAG_UNUSED,
+    [MB_ASHGRASS]                        = TILE_FLAG_UNUSED | TILE_FLAG_HAS_ENCOUNTERS,
+    [MB_FOOTPRINTS]                      = TILE_FLAG_UNUSED | TILE_FLAG_HAS_ENCOUNTERS,
+    [MB_THIN_ICE]                        = TILE_FLAG_UNUSED,
+    [MB_CRACKED_ICE]                     = TILE_FLAG_UNUSED,
+    [MB_HOT_SPRINGS]                     = TILE_FLAG_UNUSED,
+    [MB_LAVARIDGE_GYM_B1F_WARP]          = TILE_FLAG_UNUSED,
+    [MB_SEAWEED_NO_SURFACING]            = TILE_FLAG_UNUSED | TILE_FLAG_SURFABLE | TILE_FLAG_HAS_ENCOUNTERS,
+    [MB_REFLECTION_UNDER_BRIDGE]         = TILE_FLAG_UNUSED,
+    [MB_IMPASSABLE_EAST]                 = TILE_FLAG_UNUSED,
+    [MB_IMPASSABLE_WEST]                 = TILE_FLAG_UNUSED,
+    [MB_IMPASSABLE_NORTH]                = TILE_FLAG_UNUSED,
+    [MB_IMPASSABLE_SOUTH]                = TILE_FLAG_UNUSED,
+    [MB_IMPASSABLE_NORTHEAST]            = TILE_FLAG_UNUSED,
+    [MB_IMPASSABLE_NORTHWEST]            = TILE_FLAG_UNUSED,
+    [MB_IMPASSABLE_SOUTHEAST]            = TILE_FLAG_UNUSED,
+    [MB_IMPASSABLE_SOUTHWEST]            = TILE_FLAG_UNUSED,
+    [MB_JUMP_NORTHEAST]                  = TILE_FLAG_UNUSED,
+    [MB_JUMP_NORTHWEST]                  = TILE_FLAG_UNUSED,
+    [MB_JUMP_SOUTHEAST]                  = TILE_FLAG_UNUSED,
+    [MB_JUMP_SOUTHWEST]                  = TILE_FLAG_UNUSED,
+    [MB_WALK_EAST]                       = TILE_FLAG_UNUSED,
+    [MB_WALK_WEST]                       = TILE_FLAG_UNUSED,
+    [MB_WALK_NORTH]                      = TILE_FLAG_UNUSED,
+    [MB_WALK_SOUTH]                      = TILE_FLAG_UNUSED,
+    [MB_SLIDE_EAST]                      = TILE_FLAG_UNUSED,
+    [MB_SLIDE_WEST]                      = TILE_FLAG_UNUSED,
+    [MB_SLIDE_NORTH]                     = TILE_FLAG_UNUSED,
+    [MB_SLIDE_SOUTH]                     = TILE_FLAG_UNUSED,
+    [MB_TRICK_HOUSE_PUZZLE_8_FLOOR]      = TILE_FLAG_UNUSED,
+    [MB_UNUSED_49]                       = TILE_FLAG_UNUSED,
+    [MB_UNUSED_4A]                       = TILE_FLAG_UNUSED,
+    [MB_EASTWARD_CURRENT]                = TILE_FLAG_UNUSED | TILE_FLAG_SURFABLE,
+    [MB_WESTWARD_CURRENT]                = TILE_FLAG_UNUSED | TILE_FLAG_SURFABLE,
+    [MB_NORTHWARD_CURRENT]               = TILE_FLAG_UNUSED | TILE_FLAG_SURFABLE,
+    [MB_SOUTHWARD_CURRENT]               = TILE_FLAG_UNUSED | TILE_FLAG_SURFABLE,
+    [MB_NON_ANIMATED_DOOR]               = TILE_FLAG_UNUSED,
+    [MB_LADDER]                          = TILE_FLAG_UNUSED,
+    [MB_EAST_ARROW_WARP]                 = TILE_FLAG_UNUSED,
+    [MB_WEST_ARROW_WARP]                 = TILE_FLAG_UNUSED,
+    [MB_NORTH_ARROW_WARP]                = TILE_FLAG_UNUSED,
+    [MB_SOUTH_ARROW_WARP]                = TILE_FLAG_UNUSED,
+    [MB_CRACKED_FLOOR_HOLE]              = TILE_FLAG_UNUSED,
+    [MB_AQUA_HIDEOUT_WARP]               = TILE_FLAG_UNUSED,
+    [MB_LAVARIDGE_GYM_1F_WARP]           = TILE_FLAG_UNUSED,
+    [MB_ANIMATED_DOOR]                   = TILE_FLAG_UNUSED,
+    [MB_UP_ESCALATOR]                    = TILE_FLAG_UNUSED,
+    [MB_DOWN_ESCALATOR]                  = TILE_FLAG_UNUSED,
+    [MB_WATER_DOOR]                      = TILE_FLAG_UNUSED | TILE_FLAG_SURFABLE,
+    [MB_WATER_SOUTH_ARROW_WARP]          = TILE_FLAG_UNUSED | TILE_FLAG_SURFABLE,
+    [MB_DEEP_SOUTH_WARP]                 = TILE_FLAG_UNUSED,
+    [MB_UNUSED_6F]                       = TILE_FLAG_UNUSED | TILE_FLAG_SURFABLE,
+    [MB_BRIDGE_OVER_POND_LOW]            = TILE_FLAG_UNUSED,
+    [MB_BRIDGE_OVER_POND_MED]            = TILE_FLAG_UNUSED,
+    [MB_BRIDGE_OVER_POND_HIGH]           = TILE_FLAG_UNUSED,
+    [MB_PACIFIDLOG_VERTICAL_LOG_TOP]     = TILE_FLAG_UNUSED,
+    [MB_PACIFIDLOG_VERTICAL_LOG_BOTTOM]  = TILE_FLAG_UNUSED,
+    [MB_PACIFIDLOG_HORIZONTAL_LOG_LEFT]  = TILE_FLAG_UNUSED,
+    [MB_PACIFIDLOG_HORIZONTAL_LOG_RIGHT] = TILE_FLAG_UNUSED,
+    [MB_FORTREE_BRIDGE]                  = TILE_FLAG_UNUSED,
+    [MB_BRIDGE_OVER_POND_MED_EDGE_1]     = TILE_FLAG_UNUSED,
+    [MB_BRIDGE_OVER_POND_MED_EDGE_2]     = TILE_FLAG_UNUSED,
+    [MB_BRIDGE_OVER_POND_HIGH_EDGE_1]    = TILE_FLAG_UNUSED,
+    [MB_BRIDGE_OVER_POND_HIGH_EDGE_2]    = TILE_FLAG_UNUSED,
+    [MB_UNUSED_BRIDGE]                   = TILE_FLAG_UNUSED,
+    [MB_BIKE_BRIDGE_OVER_BARRIER]        = TILE_FLAG_UNUSED,
+    [MB_SECRET_BASE_SCENERY]             = TILE_FLAG_UNUSED,
+    [MB_SECRET_BASE_TRAINER_SPOT]        = TILE_FLAG_UNUSED,
+    [MB_HOLDS_SMALL_DECORATION]          = TILE_FLAG_UNUSED,
+    [MB_SECRET_BASE_BALLOON]             = TILE_FLAG_UNUSED,
+    [MB_SECRET_BASE_IMPASSABLE]          = TILE_FLAG_UNUSED,
+    [MB_SECRET_BASE_GLITTER_MAT]         = TILE_FLAG_UNUSED,
+    [MB_SECRET_BASE_JUMP_MAT]            = TILE_FLAG_UNUSED,
+    [MB_SECRET_BASE_SPIN_MAT]            = TILE_FLAG_UNUSED,
+    [MB_SECRET_BASE_SOUND_MAT]           = TILE_FLAG_UNUSED,
+    [MB_SECRET_BASE_BREAKABLE_DOOR]      = TILE_FLAG_UNUSED,
+    [MB_IMPASSABLE_SOUTH_AND_NORTH]      = TILE_FLAG_UNUSED,
+    [MB_IMPASSABLE_WEST_AND_EAST]        = TILE_FLAG_UNUSED,
+    [MB_SECRET_BASE_HOLE]                = TILE_FLAG_UNUSED,
+    [MB_HOLDS_LARGE_DECORATION]          = TILE_FLAG_UNUSED,
+    [MB_SECRET_BASE_TV_SHIELD]           = TILE_FLAG_UNUSED,
+    [MB_PLAYER_ROOM_PC_ON]               = TILE_FLAG_UNUSED,
+    [MB_MUDDY_SLOPE]                     = TILE_FLAG_UNUSED,
+    [MB_BUMPY_SLOPE]                     = TILE_FLAG_UNUSED,
+    [MB_CRACKED_FLOOR]                   = TILE_FLAG_UNUSED,
+    [MB_ISOLATED_VERTICAL_RAIL]          = TILE_FLAG_UNUSED,
+    [MB_ISOLATED_HORIZONTAL_RAIL]        = TILE_FLAG_UNUSED,
+    [MB_VERTICAL_RAIL]                   = TILE_FLAG_UNUSED,
+    [MB_HORIZONTAL_RAIL]                 = TILE_FLAG_UNUSED,
 };
 
 bool8 MetatileBehavior_IsATile(u8 metatileBehavior)
@@ -259,7 +134,7 @@ bool8 MetatileBehavior_IsATile(u8 metatileBehavior)
 
 bool8 MetatileBehavior_IsEncounterTile(u8 metatileBehavior)
 {
-    if ((sTileBitAttributes[metatileBehavior] & TILE_FLAG_ENCOUNTER_TILE))
+    if ((sTileBitAttributes[metatileBehavior] & TILE_FLAG_HAS_ENCOUNTERS))
         return TRUE;
     else
         return FALSE;
@@ -687,17 +562,19 @@ bool8 MetatileBehavior_IsRecordMixingSecretBasePC(u8 metatileBehavior)
         return FALSE;
 }
 
-bool8 Unref_MetatileBehavior_IsSecretBaseUnused_B2(u8 metatileBehavior)
+// Used by the rock/grass floor spaces that the secret base trainer is not standing on
+bool8 MetatileBehavior_IsSecretBaseScenery1(u8 metatileBehavior)
 {
-    if (metatileBehavior == MB_SECRET_BASE_UNUSED)
+    if (metatileBehavior == MB_SECRET_BASE_SCENERY)
         return TRUE;
     else
         return FALSE;
 }
 
-bool8 MetatileBehavior_IsBlockDecoration(u8 metatileBehavior)
+// Used by the rock/grass floor space that the secret base trainer stands on
+bool8 MetatileBehavior_IsSecretBaseTrainerSpot(u8 metatileBehavior)
 {
-    if (metatileBehavior == MB_BLOCK_DECORATION)
+    if (metatileBehavior == MB_SECRET_BASE_TRAINER_SPOT)
         return TRUE;
     else
         return FALSE;
@@ -743,9 +620,9 @@ bool8 MetatileBehavior_IsSecretBaseNorthWall(u8 metatileBehavior)
         return FALSE;
 }
 
-bool8 Unref_MetatileBehavior_IsSecretBaseUnused_B2_2(u8 metatileBehavior)
+bool8 MetatileBehavior_IsSecretBaseScenery2(u8 metatileBehavior)
 {
-    if (metatileBehavior == MB_SECRET_BASE_UNUSED)
+    if (metatileBehavior == MB_SECRET_BASE_SCENERY)
         return TRUE;
     else
         return FALSE;
diff --git a/src/overworld.c b/src/overworld.c
index 4aa579fdd..ba6eaa167 100644
--- a/src/overworld.c
+++ b/src/overworld.c
@@ -183,9 +183,9 @@ static u16 (*sPlayerKeyInterceptCallback)(u32);
 static bool8 sReceivingFromLink;
 static u8 sRfuKeepAliveTimer;
 
-u16 *gBGTilemapBuffers1;
-u16 *gBGTilemapBuffers2;
-u16 *gBGTilemapBuffers3;
+u16 *gOverworldTilemapBuffer_Bg2;
+u16 *gOverworldTilemapBuffer_Bg1;
+u16 *gOverworldTilemapBuffer_Bg3;
 u16 gHeldKeyCodeToSend;
 void (*gFieldCallback)(void);
 bool8 (*gFieldCallback2)(void);
@@ -1394,12 +1394,12 @@ static void InitOverworldBgs(void)
     SetBgAttribute(1, BG_ATTR_MOSAIC, 1);
     SetBgAttribute(2, BG_ATTR_MOSAIC, 1);
     SetBgAttribute(3, BG_ATTR_MOSAIC, 1);
-    gBGTilemapBuffers2 = AllocZeroed(BG_SCREEN_SIZE);
-    gBGTilemapBuffers1 = AllocZeroed(BG_SCREEN_SIZE);
-    gBGTilemapBuffers3 = AllocZeroed(BG_SCREEN_SIZE);
-    SetBgTilemapBuffer(1, gBGTilemapBuffers2);
-    SetBgTilemapBuffer(2, gBGTilemapBuffers1);
-    SetBgTilemapBuffer(3, gBGTilemapBuffers3);
+    gOverworldTilemapBuffer_Bg1 = AllocZeroed(BG_SCREEN_SIZE);
+    gOverworldTilemapBuffer_Bg2 = AllocZeroed(BG_SCREEN_SIZE);
+    gOverworldTilemapBuffer_Bg3 = AllocZeroed(BG_SCREEN_SIZE);
+    SetBgTilemapBuffer(1, gOverworldTilemapBuffer_Bg1);
+    SetBgTilemapBuffer(2, gOverworldTilemapBuffer_Bg2);
+    SetBgTilemapBuffer(3, gOverworldTilemapBuffer_Bg3);
     InitStandardTextBoxWindows();
 }
 
@@ -1407,12 +1407,9 @@ void CleanupOverworldWindowsAndTilemaps(void)
 {
     ClearMirageTowerPulseBlendEffect();
     FreeAllOverworldWindowBuffers();
-    if (gBGTilemapBuffers3)
-        FREE_AND_SET_NULL(gBGTilemapBuffers3);
-    if (gBGTilemapBuffers1)
-        FREE_AND_SET_NULL(gBGTilemapBuffers1);
-    if (gBGTilemapBuffers2)
-        FREE_AND_SET_NULL(gBGTilemapBuffers2);
+    TRY_FREE_AND_SET_NULL(gOverworldTilemapBuffer_Bg3);
+    TRY_FREE_AND_SET_NULL(gOverworldTilemapBuffer_Bg2);
+    TRY_FREE_AND_SET_NULL(gOverworldTilemapBuffer_Bg1);
 }
 
 static void ResetSafariZoneFlag_(void)
@@ -2695,7 +2692,7 @@ static void LoadCableClubPlayer(s32 linkPlayerId, s32 myPlayerId, struct CableCl
     GetLinkPlayerCoords(linkPlayerId, &x, &y);
     trainer->pos.x = x;
     trainer->pos.y = y;
-    trainer->pos.height = GetLinkPlayerElevation(linkPlayerId);
+    trainer->pos.elevation = GetLinkPlayerElevation(linkPlayerId);
     trainer->metatileBehavior = MapGridGetMetatileBehaviorAt(x, y);
 }
 
@@ -2748,7 +2745,7 @@ static const u8 *TryInteractWithPlayer(struct CableClubPlayer *player)
     otherPlayerPos = player->pos;
     otherPlayerPos.x += gDirectionToVectors[player->facing].x;
     otherPlayerPos.y += gDirectionToVectors[player->facing].y;
-    otherPlayerPos.height = 0;
+    otherPlayerPos.elevation = 0;
     linkPlayerId = GetLinkPlayerIdAt(otherPlayerPos.x, otherPlayerPos.y);
 
     if (linkPlayerId != MAX_LINK_PLAYERS)
@@ -2958,7 +2955,7 @@ static void InitLinkPlayerObjectEventPos(struct ObjectEvent *objEvent, s16 x, s1
     objEvent->previousCoords.y = y;
     SetSpritePosToMapCoords(x, y, &objEvent->initialCoords.x, &objEvent->initialCoords.y);
     objEvent->initialCoords.x += 8;
-    ObjectEventUpdateZCoord(objEvent);
+    ObjectEventUpdateElevation(objEvent);
 }
 
 static void SetLinkPlayerObjectRange(u8 linkPlayerId, u8 dir)
@@ -3098,7 +3095,7 @@ static bool8 FacingHandler_DpadMovement(struct LinkPlayerObjectEvent *linkPlayer
     {
         objEvent->directionSequenceIndex = 16;
         ShiftObjectEventCoords(objEvent, x, y);
-        ObjectEventUpdateZCoord(objEvent);
+        ObjectEventUpdateElevation(objEvent);
         return TRUE;
     }
 }
@@ -3204,8 +3201,8 @@ static void SpriteCB_LinkPlayer(struct Sprite *sprite)
     struct ObjectEvent *objEvent = &gObjectEvents[linkPlayerObjEvent->objEventId];
     sprite->x = objEvent->initialCoords.x;
     sprite->y = objEvent->initialCoords.y;
-    SetObjectSubpriorityByZCoord(objEvent->previousElevation, sprite, 1);
-    sprite->oam.priority = ZCoordToPriority(objEvent->previousElevation);
+    SetObjectSubpriorityByElevation(objEvent->previousElevation, sprite, 1);
+    sprite->oam.priority = ElevationToPriority(objEvent->previousElevation);
 
     if (linkPlayerObjEvent->movementMode == MOVEMENT_MODE_FREE)
         StartSpriteAnim(sprite, GetFaceDirectionAnimNum(linkDirection(objEvent)));
diff --git a/src/scrcmd.c b/src/scrcmd.c
index 4b7477fe1..44bd14c28 100644
--- a/src/scrcmd.c
+++ b/src/scrcmd.c
@@ -2046,7 +2046,7 @@ bool8 ScrCmd_setmetatile(struct ScriptContext *ctx)
     if (!isImpassable)
         MapGridSetMetatileIdAt(x, y, tileId);
     else
-        MapGridSetMetatileIdAt(x, y, tileId | METATILE_COLLISION_MASK);
+        MapGridSetMetatileIdAt(x, y, tileId | MAPGRID_COLLISION_MASK);
     return FALSE;
 }
 
diff --git a/src/secret_base.c b/src/secret_base.c
index 8fc97141f..9398c4bb2 100644
--- a/src/secret_base.c
+++ b/src/secret_base.c
@@ -305,7 +305,7 @@ static void FindMetatileIdMapCoords(s16 *x, s16 *y, u16 metatileId)
     {
         for (i = 0; i < mapLayout->width; i++)
         {
-            if ((mapLayout->map[j * mapLayout->width + i] & METATILE_ID_MASK) == metatileId)
+            if ((mapLayout->map[j * mapLayout->width + i] & MAPGRID_METATILE_ID_MASK) == metatileId)
             {
                 *x = i;
                 *y = j;
@@ -330,7 +330,7 @@ void ToggleSecretBaseEntranceMetatile(void)
     {
         if (sSecretBaseEntranceMetatiles[i].closedMetatileId == metatileId)
         {
-            MapGridSetMetatileIdAt(x, y, sSecretBaseEntranceMetatiles[i].openMetatileId | METATILE_COLLISION_MASK);
+            MapGridSetMetatileIdAt(x, y, sSecretBaseEntranceMetatiles[i].openMetatileId | MAPGRID_COLLISION_MASK);
             CurrentMapDrawMetatileAt(x, y);
             return;
         }
@@ -341,7 +341,7 @@ void ToggleSecretBaseEntranceMetatile(void)
     {
         if (sSecretBaseEntranceMetatiles[i].openMetatileId == metatileId)
         {
-            MapGridSetMetatileIdAt(x, y, sSecretBaseEntranceMetatiles[i].closedMetatileId | METATILE_COLLISION_MASK);
+            MapGridSetMetatileIdAt(x, y, sSecretBaseEntranceMetatiles[i].closedMetatileId | MAPGRID_COLLISION_MASK);
             CurrentMapDrawMetatileAt(x, y);
             return;
         }
@@ -396,7 +396,7 @@ void SetOccupiedSecretBaseEntranceMetatiles(struct MapEvents const *events)
                     {
                         if (sSecretBaseEntranceMetatiles[i].closedMetatileId == tile_id)
                         {
-                            MapGridSetMetatileIdAt(x, y, sSecretBaseEntranceMetatiles[i].openMetatileId | METATILE_COLLISION_MASK);
+                            MapGridSetMetatileIdAt(x, y, sSecretBaseEntranceMetatiles[i].openMetatileId | MAPGRID_COLLISION_MASK);
                             break;
                         }
                     }
@@ -475,7 +475,7 @@ static void EnterNewlyCreatedSecretBase_StartFadeIn(void)
     FindMetatileIdMapCoords(&x, &y, METATILE_SecretBase_PC);
     x += MAP_OFFSET;
     y += MAP_OFFSET;
-    MapGridSetMetatileIdAt(x, y, METATILE_SecretBase_PC | METATILE_COLLISION_MASK);
+    MapGridSetMetatileIdAt(x, y, METATILE_SecretBase_PC | MAPGRID_COLLISION_MASK);
     CurrentMapDrawMetatileAt(x, y);
     FadeInFromBlack();
     CreateTask(EnterNewlyCreatedSecretBase_WaitFadeIn, 0);
@@ -536,13 +536,13 @@ void InitSecretBaseAppearance(bool8 hidePC)
         {
             // Another player's secret base. Change PC type to the "Register" PC.
             FindMetatileIdMapCoords(&x, &y, METATILE_SecretBase_PC);
-            MapGridSetMetatileIdAt(x + MAP_OFFSET, y + MAP_OFFSET, METATILE_SecretBase_RegisterPC | METATILE_COLLISION_MASK);
+            MapGridSetMetatileIdAt(x + MAP_OFFSET, y + MAP_OFFSET, METATILE_SecretBase_RegisterPC | MAPGRID_COLLISION_MASK);
         }
         else if (hidePC == TRUE && VarGet(VAR_SECRET_BASE_INITIALIZED) == 1)
         {
             // Change PC to regular ground tile.
             FindMetatileIdMapCoords(&x, &y, METATILE_SecretBase_PC);
-            MapGridSetMetatileIdAt(x + MAP_OFFSET, y + MAP_OFFSET, METATILE_SecretBase_Ground | METATILE_COLLISION_MASK);
+            MapGridSetMetatileIdAt(x + MAP_OFFSET, y + MAP_OFFSET, METATILE_SecretBase_Ground | MAPGRID_COLLISION_MASK);
         }
     }
 }
@@ -838,7 +838,7 @@ static void ClosePlayerSecretBaseEntrance(void)
                 {
                     MapGridSetMetatileIdAt(events->bgEvents[i].x + MAP_OFFSET,
                                            events->bgEvents[i].y + MAP_OFFSET,
-                                           sSecretBaseEntranceMetatiles[j].closedMetatileId | METATILE_COLLISION_MASK);
+                                           sSecretBaseEntranceMetatiles[j].closedMetatileId | MAPGRID_COLLISION_MASK);
                     break;
                 }
             }
diff --git a/src/shop.c b/src/shop.c
index b65cace09..700a53e37 100755
--- a/src/shop.c
+++ b/src/shop.c
@@ -743,7 +743,7 @@ static void BuyMenuDrawMapBg(void)
             if (BuyMenuCheckForOverlapWithMenuBg(i, j) == TRUE)
                 metatileLayerType = MapGridGetMetatileLayerTypeAt(x + i, y + j);
             else
-                metatileLayerType = 1;
+                metatileLayerType = METATILE_LAYER_TYPE_COVERED;
 
             if (metatile < NUM_METATILES_IN_PRIMARY)
             {
@@ -764,15 +764,15 @@ static void BuyMenuDrawMapMetatile(s16 x, s16 y, const u16 *src, u8 metatileLaye
 
     switch (metatileLayerType)
     {
-    case 0:
+    case METATILE_LAYER_TYPE_NORMAL:
         BuyMenuDrawMapMetatileLayer(sShopData->tilemapBuffers[3], offset1, offset2, src);
         BuyMenuDrawMapMetatileLayer(sShopData->tilemapBuffers[1], offset1, offset2, src + 4);
         break;
-    case 1:
+    case METATILE_LAYER_TYPE_COVERED:
         BuyMenuDrawMapMetatileLayer(sShopData->tilemapBuffers[2], offset1, offset2, src);
         BuyMenuDrawMapMetatileLayer(sShopData->tilemapBuffers[3], offset1, offset2, src + 4);
         break;
-    case 2:
+    case METATILE_LAYER_TYPE_SPLIT:
         BuyMenuDrawMapMetatileLayer(sShopData->tilemapBuffers[2], offset1, offset2, src);
         BuyMenuDrawMapMetatileLayer(sShopData->tilemapBuffers[1], offset1, offset2, src + 4);
         break;
@@ -866,7 +866,7 @@ static void BuyMenuDrawObjectEvents(void)
 
 static bool8 BuyMenuCheckIfObjectEventOverlapsMenuBg(s16 *object)
 {
-    if (!BuyMenuCheckForOverlapWithMenuBg(object[X_COORD], object[Y_COORD] + 2) && object[LAYER_TYPE] != MB_SECRET_BASE_WALL)
+    if (!BuyMenuCheckForOverlapWithMenuBg(object[X_COORD], object[Y_COORD] + 2) && object[LAYER_TYPE] != METATILE_LAYER_TYPE_COVERED)
     {
         return TRUE;
     }
diff --git a/src/trainer_hill.c b/src/trainer_hill.c
index 8d5be0116..39c6202a0 100644
--- a/src/trainer_hill.c
+++ b/src/trainer_hill.c
@@ -677,9 +677,9 @@ static u16 GetMetatileForFloor(u8 floorId, u32 x, u32 y, u32 stride) // stride i
 
     impassable = (sHillData->floors[floorId].display.collisionData[y] >> (15 - x) & 1);
     metatile = sHillData->floors[floorId].display.metatileData[stride * y + x] + NUM_METATILES_IN_PRIMARY;
-    elevation = 3 << METATILE_ELEVATION_SHIFT;
+    elevation = 3 << MAPGRID_ELEVATION_SHIFT;
 
-    return ((impassable << METATILE_COLLISION_SHIFT) & METATILE_COLLISION_MASK) | elevation | (metatile & METATILE_ID_MASK);
+    return ((impassable << MAPGRID_COLLISION_SHIFT) & MAPGRID_COLLISION_MASK) | elevation | (metatile & MAPGRID_METATILE_ID_MASK);
 }
 
 void GenerateTrainerHillFloorLayout(u16 *mapArg)
diff --git a/src/tv.c b/src/tv.c
index 710b98968..b9d064026 100644
--- a/src/tv.c
+++ b/src/tv.c
@@ -852,7 +852,7 @@ void UpdateTVScreensOnMap(int width, int height)
     }
 }
 
-static void SetTVMetatilesOnMap(int width, int height, u16 tileId)
+static void SetTVMetatilesOnMap(int width, int height, u16 metatileId)
 {
     int x;
     int y;
@@ -862,7 +862,7 @@ static void SetTVMetatilesOnMap(int width, int height, u16 tileId)
         for (x = 0; x < width; x++)
         {
             if (MapGridGetMetatileBehaviorAt(x, y) == MB_TELEVISION)
-                MapGridSetMetatileIdAt(x, y, tileId | METATILE_COLLISION_MASK);
+                MapGridSetMetatileIdAt(x, y, metatileId | MAPGRID_COLLISION_MASK);
         }
     }
 }