Cleanup and document daycare.c

12 files changed, 532 insertions, 425 deletions

diff --git a/data/scripts/day_care.inc b/data/scripts/day_care.inc
index f8151b86a..22d99f2a4 100644
--- a/data/scripts/day_care.inc
+++ b/data/scripts/day_care.inc
@@ -1,8 +1,8 @@
 Route117_EventScript_1B222D:: @ 81B222D
 	lock
 	faceplayer
-	special sp0B5_daycare
-	specialvar RESULT, sp0B6_daycare
+	special GetDaycareMonNicknames
+	specialvar RESULT, GetDaycareState
 	compare RESULT, 1
 	goto_if_eq Route117_EventScript_1B2262
 	compare RESULT, 2
@@ -22,7 +22,7 @@ Route117_EventScript_1B2262:: @ 81B2262
 	goto_if_eq Route117_EventScript_1B2298
 	msgbox Route117_Text_1B2745, 4
 	clearflag 134
-	special sub_8041E7C
+	special RejectEggFromDayCare
 	release
 	end
 
@@ -41,7 +41,7 @@ Route117_EventScript_1B22B2:: @ 81B22B2
 	waitmessage
 	waitbutton
 	msgbox Route117_Text_1B27CD, 4
-	special sp0B8_daycare
+	special GiveEggFromDaycare
 	clearflag 134
 	release
 	end
@@ -57,7 +57,7 @@ Route117_EventScript_1B22DE:: @ 81B22DE
 	return
 
 Route117_EventScript_1B22E7:: @ 81B22E7
-	special sp0B5_daycare
+	special GetDaycareMonNicknames
 	msgbox Route117_Text_1B2710, 4
 	setvar 0x8004, 0
 	call Route117_EventScript_1B22CD
@@ -65,9 +65,9 @@ Route117_EventScript_1B22E7:: @ 81B22E7
 	end
 
 Route117_EventScript_1B22FE:: @ 81B22FE
-	special sp0B5_daycare
+	special GetDaycareMonNicknames
 	msgbox Route117_Text_1B2897, 4
-	special sp0B9_daycare_relationship_comment
+	special SetDaycareCompatibilityString
 	special ShowFieldMessageStringVar4
 	waitmessage
 	waitbutton
@@ -81,7 +81,7 @@ Route117_EventScript_1B22FE:: @ 81B22FE
 Route117_PokemonDayCare_EventScript_1B2327:: @ 81B2327
 	lock
 	faceplayer
-	specialvar RESULT, sp0B6_daycare
+	specialvar RESULT, GetDaycareState
 	compare RESULT, 1
 	goto_if_eq Route117_PokemonDayCare_EventScript_1B2407
 	compare RESULT, 2
@@ -108,14 +108,14 @@ Route117_PokemonDayCare_EventScript_1B236C:: @ 81B236C
 	specialvar RESULT, sub_8095C10
 	compare RESULT, 0
 	goto_if_eq Route117_PokemonDayCare_EventScript_1B23FD
-	specialvar 0x8005, sub_8042328
+	specialvar 0x8005, GetSelectedDaycareMonNickname
 	waitse
 	playpokecry 0x8005, 0
 	msgbox Route117_PokemonDayCare_Text_1B296E, 4
 	waitpokecry
-	special Daycare_SendPokemon_Special
+	special StoreSelectedPokemonInDaycare
 	incrementgamestat GAME_STAT_USED_DAYCARE
-	specialvar RESULT, sp0B6_daycare
+	specialvar RESULT, GetDaycareState
 	compare RESULT, 2
 	goto_if_eq Route117_PokemonDayCare_EventScript_1B23DA
 	release
@@ -153,7 +153,7 @@ Route117_PokemonDayCare_EventScript_1B2411:: @ 81B2411
 	return
 
 Route117_PokemonDayCare_EventScript_1B241A:: @ 81B241A
-	specialvar RESULT, sub_80417B8
+	specialvar RESULT, GetNumLevelsGainedFromDaycare
 	compare RESULT, 0
 	call_if 5, Route117_PokemonDayCare_EventScript_1B2411
 	return
@@ -175,7 +175,7 @@ Route117_PokemonDayCare_EventScript_1B2469:: @ 81B2469
 	specialvar RESULT, CalculatePlayerPartyCount
 	compare RESULT, 6
 	goto_if_eq Route117_PokemonDayCare_EventScript_1B2539
-	specialvar RESULT, sp0B6_daycare
+	specialvar RESULT, GetDaycareState
 	setvar 0x8004, 0
 	compare RESULT, 2
 	goto_if_eq Route117_PokemonDayCare_EventScript_1B24A8
@@ -188,7 +188,7 @@ Route117_PokemonDayCare_EventScript_1B2469:: @ 81B2469
 	end
 
 Route117_PokemonDayCare_EventScript_1B24A8:: @ 81B24A8
-	special sub_8041770
+	special GetDaycareCost
 	msgbox Route117_PokemonDayCare_Text_1B2B49, 5
 	compare RESULT, 1
 	goto_if_eq Route117_PokemonDayCare_EventScript_1B24C4
@@ -206,7 +206,7 @@ Route117_PokemonDayCare_EventScript_1B24C4:: @ 81B24C4
 Route117_PokemonDayCare_EventScript_1B24DE:: @ 81B24DE
 	applymovement 1, Route117_PokemonDayCare_Movement_1B2543
 	waitmovement 0
-	specialvar RESULT, sub_8041648
+	specialvar RESULT, TakePokemonFromDaycare
 	special sub_80B7D0C
 	playse 95
 	msgbox Route117_PokemonDayCare_Text_1B2B75, 4
@@ -214,7 +214,7 @@ Route117_PokemonDayCare_EventScript_1B24DE:: @ 81B24DE
 	playpokecry RESULT, 0
 	msgbox Route117_PokemonDayCare_Text_1B2B93, 4
 	waitpokecry
-	specialvar RESULT, sp0B6_daycare
+	specialvar RESULT, GetDaycareState
 	compare RESULT, 2
 	goto_if_eq Route117_PokemonDayCare_EventScript_1B2520
 	goto Route117_PokemonDayCare_EventScript_1B23D0
@@ -276,7 +276,7 @@ Route117_PokemonDayCare_EventScript_1B2558:: @ 81B2558
 	compare RESULT, 2
 	goto_if_eq Route117_PokemonDayCare_EventScript_1B23D0
 	copyvar 0x8004, RESULT
-	specialvar RESULT, sub_8041648
+	specialvar RESULT, TakePokemonFromDaycare
 	msgbox Route117_PokemonDayCare_Text_1B2B75, 4
 	msgbox Route117_PokemonDayCare_Text_1B2A76, 4
 	release
diff --git a/data/specials.inc b/data/specials.inc
index 0b3648c4a..efa8da174 100644
--- a/data/specials.inc
+++ b/data/specials.inc
@@ -188,18 +188,18 @@ gSpecials::
 	def_special sub_80BDD18
 	def_special GabbyAndTySetScriptVarsToFieldObjectLocalIds
 	def_special sub_810E300
-	def_special sp0B5_daycare
-	def_special sp0B6_daycare
-	def_special sub_8041E7C
-	def_special sp0B8_daycare
-	def_special sp0B9_daycare_relationship_comment
-	def_special sub_8042328
-	def_special Daycare_SendPokemon_Special
+	def_special GetDaycareMonNicknames
+	def_special GetDaycareState
+	def_special RejectEggFromDayCare
+	def_special GiveEggFromDaycare
+	def_special SetDaycareCompatibilityString
+	def_special GetSelectedDaycareMonNickname
+	def_special StoreSelectedPokemonInDaycare
 	def_special ChooseSendDaycareMon
 	def_special ShowDaycareLevelMenu
-	def_special sub_80417B8
-	def_special sub_8041770
-	def_special sub_8041648
+	def_special GetNumLevelsGainedFromDaycare
+	def_special GetDaycareCost
+	def_special TakePokemonFromDaycare
 	def_special ScriptHatchMon
 	def_special EggHatch
 	def_special sub_8042B4C
diff --git a/include/daycare.h b/include/daycare.h
index e46351d72..c612113b9 100644
--- a/include/daycare.h
+++ b/include/daycare.h
@@ -1,15 +1,17 @@
 #ifndef GUARD_DAYCARE_H
 #define GUARD_DAYCARE_H
 
-u8 Daycare_CountPokemon(struct DayCareData *);
-void sub_8041324(struct BoxPokemon *, struct RecordMixingDayCareMail *);
-void sub_8041790(u16 i);
-u16 sub_8041870(u16);
-void sub_8041940(void);
-void sub_8041950(void);
-void sub_8042044(struct Pokemon *mon, u16, u8);
-u8 sub_80422A0(void);
-u8 daycare_relationship_score_from_savegame(void);
+u8 *GetMonNick(struct Pokemon *, u8 *);
+u8 *GetBoxMonNick(struct BoxPokemon *, u8 *);
+u8 CountPokemonInDaycare(struct DayCare *);
+void InitDaycareMailRecordMixing(struct BoxPokemon *, struct RecordMixingDayCareMail *);
+void Debug_AddDaycareSteps(u16 i);
+u16 GetEggSpecies(u16);
+void TriggerPendingDaycareEgg(void);
+void TriggerPendingDaycareMaleEgg(void);
+void CreateEgg(struct Pokemon *mon, u16, u8);
+u8 ShouldEggHatch(void);
+u8 GetDaycareCompatibilityScoreFromSave(void);
 bool8 NameHasGenderSymbol(const u8 *, u8);
 
 #endif // GUARD_DAYCARE_H
diff --git a/include/flags.h b/include/flags.h
index a60de6ea0..83fcdb383 100644
--- a/include/flags.h
+++ b/include/flags.h
@@ -1,6 +1,9 @@
 #ifndef GUARD_FLAGS_H
 #define GUARD_FLAGS_H
 
+// scripts
+#define FLAG_PENDING_DAYCARE_EGG 0x86
+
 #define TRAINER_FLAG_START 0x500
 
 // SYSTEM FLAGS
diff --git a/include/global.h b/include/global.h
index 647f66bc8..4921cf977 100644
--- a/include/global.h
+++ b/include/global.h
@@ -587,15 +587,15 @@ struct DayCareMail
 
 struct DayCareStepCountersEtc {
     u32 steps[2];
-    u16 personalityLo;
-    u8 unk_11a;
+    u16 pendingEggPersonality;
+    u8 eggCycleStepsRemaining;
 };
 
 struct RecordMixingDayCareMail
 {
     struct DayCareMail mail[2];
-    u32 unk70;
-    u16 unk74[2];
+    u32 numDaycareMons;
+    u16 itemsHeld[2]; // marks whether or not each daycare mon is currently holding an item.
 };
 
 struct DayCareMisc
@@ -604,7 +604,7 @@ struct DayCareMisc
     struct DayCareStepCountersEtc countersEtc;
 };
 
-struct DayCareData {
+struct DayCare {
     struct BoxPokemon mons[2];
     struct DayCareMisc misc;
 };
@@ -712,7 +712,7 @@ struct SaveBlock1 /* 0x02025734 */
     /*0x2DD4*/ struct EasyChatPair easyChatPairs[5]; //Dewford trend [0] and some other stuff
     /*0x2DFC*/ u8 filler_2DFC[0x8];
     /*0x2E04*/ SB_Struct sbStruct;
-    /*0x2F9C*/ struct DayCareData daycareData;
+    /*0x2F9C*/ struct DayCare daycare;
     /*0x30B8*/ struct LinkBattleRecord linkBattleRecords[5];
     /*0x3108*/ u8 filler_3108[8];
     /*0x3110*/ u8 giftRibbons[11];
diff --git a/src/debug/mori_debug_menu.c b/src/debug/mori_debug_menu.c
index 1595ecd2e..e6ee243e8 100644
--- a/src/debug/mori_debug_menu.c
+++ b/src/debug/mori_debug_menu.c
@@ -50,13 +50,13 @@ u8 MoriDebugMenu_SearchChild(u8 a1, u8 a2, u8 *ptr)
 {
     u8 localPtr[52];
     u16 monData;
-    u16 var;
+    u16 eggSpecies;
 
     monData = GetMonData(gPlayerParty, MON_DATA_SPECIES, ptr);
-    var = sub_8041870(monData);
+    eggSpecies = GetEggSpecies(monData);
     StringCopy(localPtr, gSpeciesNames[monData]);
     StringAppend(localPtr, gUnknown_0839B24D);
-    StringAppend(localPtr, gSpeciesNames[var]);
+    StringAppend(localPtr, gSpeciesNames[eggSpecies]);
     StringAppend(localPtr, gUnknown_0839B255);
     MenuZeroFillScreen();
     MenuDrawTextWindow(0, 14, 30, 19);
@@ -67,8 +67,8 @@ u8 MoriDebugMenu_SearchChild(u8 a1, u8 a2, u8 *ptr)
 
 s8 MoriDebugMenu_Egg(void)
 {
-    if ( Daycare_CountPokemon(&gSaveBlock1.daycareData) == 2 && daycare_relationship_score_from_savegame() )
-        sub_8041940();
+    if (CountPokemonInDaycare(&gSaveBlock1.daycare) == 2 && GetDaycareCompatibilityScoreFromSave() )
+        TriggerPendingDaycareEgg();
     CloseMenu();
 
     return 1;
@@ -76,8 +76,8 @@ s8 MoriDebugMenu_Egg(void)
 
 s8 MoriDebugMenu_MaleEgg(void)
 {
-    if ( Daycare_CountPokemon(&gSaveBlock1.daycareData) == 2 && daycare_relationship_score_from_savegame() )
-        sub_8041950();
+    if (CountPokemonInDaycare(&gSaveBlock1.daycare) == 2 && GetDaycareCompatibilityScoreFromSave() )
+        TriggerPendingDaycareMaleEgg();
     CloseMenu();
 
     return 1;
@@ -85,14 +85,14 @@ s8 MoriDebugMenu_MaleEgg(void)
 
 s8 MoriDebugMenu_1000Steps(void)
 {
-    sub_8041790(1000);
+    Debug_AddDaycareSteps(1000);
     CloseMenu();
     return 1;
 }
 
 s8 MoriDebugMenu_10000Steps(void)
 {
-    sub_8041790(10000);
+    Debug_AddDaycareSteps(10000);
     CloseMenu();
     return 1;
 }
@@ -117,7 +117,7 @@ s8 MoriDebugMenu_BreedEgg(void)
             SetMonData(&gPlayerParty[loopCounter], MON_DATA_FRIENDSHIP, &friendship);
         }
     }
-    gSaveBlock1.daycareData.misc.countersEtc.unk_11a = -3;
+    gSaveBlock1.daycare.misc.countersEtc.eggCycleStepsRemaining = -3;
     CloseMenu();
     return 1;
 }
diff --git a/src/engine/record_mixing.c b/src/engine/record_mixing.c
index 3ae0c4ea3..b30d57a4d 100644
--- a/src/engine/record_mixing.c
+++ b/src/engine/record_mixing.c
@@ -71,9 +71,9 @@ void RecordMixing_PrepareExchangePacket(void)
     memcpy(ewram_2018000.filler1004, gUnknown_083D0274, sizeof(ewram_2008000.filler1004));
     memcpy(ewram_2018000.filler1044, gUnknown_083D0278, sizeof(ewram_2008000.filler1044));
     memcpy(ewram_2018000.easyChatPairs, recordMixingEasyChatPairs, sizeof(ewram_2018000.easyChatPairs));
-    gUnknown_02038738.mail[0] = gSaveBlock1.daycareData.misc.mail[0];
-    gUnknown_02038738.mail[1] = gSaveBlock1.daycareData.misc.mail[1];
-    sub_8041324(gSaveBlock1.daycareData.mons, &gUnknown_02038738);
+    gUnknown_02038738.mail[0] = gSaveBlock1.daycare.misc.mail[0];
+    gUnknown_02038738.mail[1] = gSaveBlock1.daycare.misc.mail[1];
+    InitDaycareMailRecordMixing(gSaveBlock1.daycare.mons, &gUnknown_02038738);
     memcpy(&ewram_2018000.filler10AC, gUnknown_083D0280, sizeof(struct RecordMixingDayCareMail));
     memcpy(&ewram_2018000.battleTowerRecord, gBattleTowerPlayerRecord, sizeof(struct BattleTowerRecord));
 
@@ -524,11 +524,11 @@ void sub_80B9C6C(u8 *a, u32 b, u8 c, void *d)
     for (i = 0; i < r8; i++)
     {
         r6 = (struct DayCareMisc *)(a + b * i);
-        if (r6->unk70 != 0)
+        if (r6->numDaycareMons != 0)
         {
-            for (r7 = 0; r7 < r6->unk70; r7++)
+            for (r7 = 0; r7 < r6->numDaycareMons; r7++)
             {
-                if (r6->unk74[r7] == 0)
+                if (r6->itemsHeld[r7] == 0)
                     sp1C[i][r7] = 1;
             }
         }
diff --git a/src/field/daycare.c b/src/field/daycare.c
index dd74f59e0..2b58a0d5d 100644
--- a/src/field/daycare.c
+++ b/src/field/daycare.c
@@ -1,47 +1,50 @@
 #include "global.h"
 #include "daycare.h"
-#include "pokemon.h"
 #include "event_data.h"
-#include "species.h"
+#include "field_effect.h"
 #include "items.h"
-#include "text.h"
-#include "string_util.h"
 #include "mail_data.h"
+#include "main.h"
+#include "menu.h"
+#include "moves.h"
 #include "name_string_util.h"
+#include "overworld.h"
+#include "party_menu.h"
+#include "pokemon.h"
 #include "pokemon_storage_system.h"
 #include "rng.h"
-#include "moves.h"
-#include "trade.h"
-#include "strings2.h"
-#include "party_menu.h"
-#include "field_effect.h"
-#include "main.h"
-#include "menu.h"
-#include "sound.h"
-#include "songs.h"
 #include "script.h"
-#include "overworld.h"
+#include "songs.h"
+#include "sound.h"
+#include "species.h"
+#include "string_util.h"
+#include "strings2.h"
+#include "text.h"
+#include "trade.h"
 
-IWRAM_DATA u16 gUnknown_03000470[52];
-IWRAM_DATA u16 gUnknown_030004D8[4];
-IWRAM_DATA u16 gUnknown_030004E0[4];
-IWRAM_DATA u16 gUnknown_030004E8[12];
-IWRAM_DATA u16 gUnknown_03000500[4];
+// RAM buffers used to assist with BuildEggMoveset()
+IWRAM_DATA u16 gHatchedEggLevelUpMoves[52];
+IWRAM_DATA u16 gHatchedEggFatherMoves[4];
+IWRAM_DATA u16 gHatchedEggFinalMoves[4];
+IWRAM_DATA u16 gHatchedEggEggMoves[12];
+IWRAM_DATA u16 gHatchedEggMotherMoves[4];
 
-static void sub_80417F4(struct DayCareMail *);
-static void sub_80420FC(struct Pokemon *, u16, struct DayCareData *);
-static u8 daycare_relationship_score(struct DayCareData *);
+extern u16 gMoveToLearn;
+
+static void ClearDaycareMail(struct DayCareMail *);
+static void SetInitialEggData(struct Pokemon *, u16, struct DayCare *);
+static u8 GetDaycareCompatibilityScore(struct DayCare *);
 
 #include "../data/pokemon/egg_moves.h"
 
-const u8 *const gUnknown_08209AC4[] = {
+static const u8 *const sCompatibilityMessages[] = {
     DaycareText_GetAlongVeryWell,
     DaycareText_GetAlong,
     DaycareText_DontLikeOther,
     DaycareText_PlayOther
 };
 
-const u8 gUnknown_08209AD4[] = _("タマゴ");
+const u8 sJapaneseEggNickname[] = _("タマゴ");
 
 u8 *GetMonNick(struct Pokemon *mon, u8 *dest)
 {
@@ -59,251 +62,284 @@ u8 *GetBoxMonNick(struct BoxPokemon *mon, u8 *dest)
     return StringCopy10(dest, nickname);
 }
 
-u8 Daycare_CountPokemon(struct DayCareData *daycare_data)
+u8 CountPokemonInDaycare(struct DayCare *daycare)
 {
     u8 i, count;
     count = 0;
 
-    for(i = 0;i <= 1;i++)
-        if(GetBoxMonData(&daycare_data->mons[i], MON_DATA_SPECIES) != 0)
+    for (i = 0; i < 2; i++)
+    {
+        if (GetBoxMonData(&daycare->mons[i], MON_DATA_SPECIES) != 0)
             count++;
+    }
 
     return count;
 }
 
-void sub_8041324(struct BoxPokemon * box_pokemon, struct RecordMixingDayCareMail * daycareMailEtc)
+void InitDaycareMailRecordMixing(struct BoxPokemon * daycareMons, struct RecordMixingDayCareMail * daycareMail)
 {
     u8 i;
-    u8 specCount;
-    specCount = 0;
-    for (i=0; i<2; i++)
+    u8 numDaycareMons = 0;
+
+    for (i = 0; i < 2; i++)
     {
-        if (GetBoxMonData(&box_pokemon[i], MON_DATA_SPECIES) != SPECIES_NONE)
+        if (GetBoxMonData(&daycareMons[i], MON_DATA_SPECIES) != SPECIES_NONE)
         {
-            specCount ++;
-            if (GetBoxMonData(&box_pokemon[i], MON_DATA_HELD_ITEM) == ITEM_NONE)
+            numDaycareMons++;
+            if (GetBoxMonData(&daycareMons[i], MON_DATA_HELD_ITEM) == ITEM_NONE)
             {
-                daycareMailEtc->unk74[i] = 0;
-            } else
+                daycareMail->itemsHeld[i] = 0;
+            }
+            else
             {
-                daycareMailEtc->unk74[i] = 1;
+                daycareMail->itemsHeld[i] = 1;
             }
-        } else
+        }
+        else
         {
-            daycareMailEtc->unk74[i] = 1;
+            daycareMail->itemsHeld[i] = 1;
         }
     }
-    daycareMailEtc->unk70 = specCount;
+
+    daycareMail->numDaycareMons = numDaycareMons;
 }
 
-static s8 Daycare_FindEmptySpot(struct BoxPokemon * daycare_data)
+static s8 Daycare_FindEmptySpot(struct BoxPokemon * daycareMons)
 {
     u8 i;
 
-    for(i = 0;i <= 1;i++)
-        if(GetBoxMonData(daycare_data + i, MON_DATA_SPECIES) == 0)
+    for (i = 0; i < 2; i++)
+    {
+        if (GetBoxMonData(&daycareMons[i], MON_DATA_SPECIES) == 0)
             return i;
+    }
 
     return -1;
 }
 
-static void Daycare_SendPokemon(struct Pokemon * mon, struct DayCareData * daycare_data)
+static void StorePokemonInDaycare(struct Pokemon * mon, struct DayCare * daycare)
 {
-    s8 empty_slot;
+    s8 emptySlot;
     u8 mail;
     u8 *names;
 
-    empty_slot = Daycare_FindEmptySpot(daycare_data->mons);
-    if(MonHasMail(mon)) {
-        StringCopy((names = daycare_data->misc.mail[empty_slot].names), gSaveBlock2.playerName);
+    emptySlot = Daycare_FindEmptySpot(daycare->mons);
+    if (MonHasMail(mon))
+    {
+        StringCopy((names = daycare->misc.mail[emptySlot].names), gSaveBlock2.playerName);
         PadNameString(names, 0xFC);
         names += 8;
         GetMonNick(mon, names);
         mail = GetMonData(mon, MON_DATA_MAIL);
-        daycare_data->misc.mail[empty_slot].message = gSaveBlock1.mail[mail];
+        daycare->misc.mail[emptySlot].message = gSaveBlock1.mail[mail];
         TakeMailFromMon(mon);
     }
-    daycare_data->mons[empty_slot] = mon->box;
-    BoxMonRestorePP(&daycare_data->mons[empty_slot]);
-    daycare_data->misc.countersEtc.steps[empty_slot] = 0;
+
+    daycare->mons[emptySlot] = mon->box;
+    BoxMonRestorePP(&daycare->mons[emptySlot]);
+    daycare->misc.countersEtc.steps[emptySlot] = 0;
     ZeroMonData(mon);
     party_compaction();
     CalculatePlayerPartyCount();
 }
 
-void Daycare_SendPokemon_Special()
+void StoreSelectedPokemonInDaycare(void)
 {
-    Daycare_SendPokemon(gPlayerParty + gLastFieldPokeMenuOpened, &gSaveBlock1.daycareData);
+    StorePokemonInDaycare(&gPlayerParty[gLastFieldPokeMenuOpened], &gSaveBlock1.daycare);
 }
 
-static void sub_80414C0(struct DayCareData * daycare_data)
+// Shifts the second daycare pokemon slot into the first slot.
+static void ShiftDaycareSlots(struct DayCare * daycare)
 {
-    if((GetBoxMonData(&daycare_data->mons[1], MON_DATA_SPECIES) != 0) && GetBoxMonData(&daycare_data->mons[0], MON_DATA_SPECIES) == 0)
+    // This condition is only satisfied when the player takes out the first pokemon from the daycare.
+    if (GetBoxMonData(&daycare->mons[1], MON_DATA_SPECIES) != 0 && GetBoxMonData(&daycare->mons[0], MON_DATA_SPECIES) == 0)
     {
-        daycare_data->mons[0] = daycare_data->mons[1];
-        ZeroBoxMonData(&daycare_data->mons[1]);
-        daycare_data->misc.mail[0] = daycare_data->misc.mail[1];
-        daycare_data->misc.countersEtc.steps[0] = daycare_data->misc.countersEtc.steps[1];
-        daycare_data->misc.countersEtc.steps[1] = 0;
-        sub_80417F4(&daycare_data->misc.mail[1]);
+        daycare->mons[0] = daycare->mons[1];
+        ZeroBoxMonData(&daycare->mons[1]);
+
+        daycare->misc.mail[0] = daycare->misc.mail[1];
+        daycare->misc.countersEtc.steps[0] = daycare->misc.countersEtc.steps[1];
+        daycare->misc.countersEtc.steps[1] = 0;
+        ClearDaycareMail(&daycare->misc.mail[1]);
     }
 }
 
-u8 TryIncrementMonLevel(struct Pokemon *);
-extern u16 gMoveToLearn;
-
-static void DayCare_LevelUpMoves(struct Pokemon * mon)
+static void ApplyDaycareExperience(struct Pokemon * mon)
 {
     s32 i;
-    u8 r6;
-    u16 temp;
+    bool8 firstMove;
+    u16 learnedMove;
 
     for (i = 0; i < MAX_LEVEL; i++)
     {
+        // Add the mon's gained daycare experience level by level until it can't level up anymore.
         if (TryIncrementMonLevel(mon))
         {
-            r6 = 1;
-            while ((temp = MonTryLearningNewMove(mon, r6)) != 0)
+            // Teach the mon new moves it learned while in the daycare.
+            firstMove = TRUE;
+            while ((learnedMove = MonTryLearningNewMove(mon, firstMove)) != 0)
             {
-                r6 = 0;
-                if (temp == 0xffff)
+                firstMove = FALSE;
+                if (learnedMove == 0xffff)
+                {
+                    // Mon already knows 4 moves.
                     DeleteFirstMoveAndGiveMoveToMon(mon, gMoveToLearn);
+                }
             }
         }
         else
+        {
             break;
+        }
     }
 
+    // Re-calculate the mons stats at its new level.
     CalculateMonStats(mon);
 }
 
-static u16 sub_8041570(struct DayCareData * daycare_data, u8 slot)
+static u16 TakeSelectedPokemonFromDaycare(struct DayCare * daycare, u8 slot)
 {
     u16 species;
     u32 experience;
     struct Pokemon pokemon;
 
-    GetBoxMonNick(&daycare_data->mons[slot], gStringVar1);
-    species = GetBoxMonData(&daycare_data->mons[slot], MON_DATA_SPECIES);
-    sub_803B4B4(&daycare_data->mons[slot], &pokemon);
+    GetBoxMonNick(&daycare->mons[slot], gStringVar1);
+    species = GetBoxMonData(&daycare->mons[slot], MON_DATA_SPECIES);
+    sub_803B4B4(&daycare->mons[slot], &pokemon);
+
     if (GetMonData(&pokemon, MON_DATA_LEVEL) != MAX_LEVEL)
     {
-        experience = GetMonData(&pokemon, MON_DATA_EXP) + daycare_data->misc.countersEtc.steps[slot];
+        experience = GetMonData(&pokemon, MON_DATA_EXP) + daycare->misc.countersEtc.steps[slot];
         SetMonData(&pokemon, MON_DATA_EXP, &experience);
-        DayCare_LevelUpMoves(&pokemon);
+        ApplyDaycareExperience(&pokemon);
     }
+
     gPlayerParty[PARTY_SIZE - 1] = pokemon;
-    if (daycare_data->misc.mail[slot].message.itemId)
+    if (daycare->misc.mail[slot].message.itemId)
     {
-        GiveMailToMon2(&gPlayerParty[PARTY_SIZE - 1], &daycare_data->misc.mail[slot].message);
-        sub_80417F4(&daycare_data->misc.mail[slot]);
+        GiveMailToMon2(&gPlayerParty[PARTY_SIZE - 1], &daycare->misc.mail[slot].message);
+        ClearDaycareMail(&daycare->misc.mail[slot]);
     }
+
     party_compaction();
-    ZeroBoxMonData(&daycare_data->mons[slot]);
-    daycare_data->misc.countersEtc.steps[slot] = 0;
-    sub_80414C0(daycare_data);
+    ZeroBoxMonData(&daycare->mons[slot]);
+    daycare->misc.countersEtc.steps[slot] = 0;
+    ShiftDaycareSlots(daycare);
     CalculatePlayerPartyCount();
     return species;
 }
 
-u16 sub_8041648()
+u16 TakePokemonFromDaycare(void)
 {
-    return sub_8041570(&gSaveBlock1.daycareData, gSpecialVar_0x8004);
+    return TakeSelectedPokemonFromDaycare(&gSaveBlock1.daycare, gSpecialVar_0x8004);
 }
 
-u8 Daycare_GetLevelAfterSteps(struct BoxPokemon * mon, u32 steps){
-    struct BoxPokemon temp = *mon;
-    u32 new_exp = GetBoxMonData(mon, MON_DATA_EXP) + steps;
-    SetBoxMonData(&temp, MON_DATA_EXP,  &new_exp);
-    return GetLevelFromBoxMonExp(&temp);
+static u8 GetLevelAfterDaycareSteps(struct BoxPokemon * mon, u32 steps)
+{
+    struct BoxPokemon tempMon = *mon;
+
+    u32 experience = GetBoxMonData(mon, MON_DATA_EXP) + steps;
+    SetBoxMonData(&tempMon, MON_DATA_EXP,  &experience);
+    return GetLevelFromBoxMonExp(&tempMon);
 }
 
-static u8 sub_80416A0(struct DayCareData *daycareData, u8 slot)
+static u8 GetNumLevelsGainedFromSteps(struct DayCare *daycare, u8 slot)
 {
     u8 levelBefore;
     u8 levelAfter;
 
-    levelBefore = GetLevelFromBoxMonExp(&daycareData->mons[slot]);
-    levelAfter = Daycare_GetLevelAfterSteps(&daycareData->mons[slot], daycareData->misc.countersEtc.steps[slot]);
+    levelBefore = GetLevelFromBoxMonExp(&daycare->mons[slot]);
+    levelAfter = GetLevelAfterDaycareSteps(&daycare->mons[slot], daycare->misc.countersEtc.steps[slot]);
     return levelAfter - levelBefore;
 }
 
-static u8 sub_80416E8(struct DayCareData *dayCareData, u8 slot)
+static u8 GetNumLevelsGainedForDaycareSlot(struct DayCare *daycare, u8 slot)
 {
-    u8 levelDelta = sub_80416A0(dayCareData, slot);
-    GetBoxMonNick(&dayCareData->mons[slot], gStringVar1);
-    ConvertIntToDecimalStringN(gStringVar2, levelDelta, STR_CONV_MODE_LEFT_ALIGN, 2);
-    return levelDelta;
+    u8 numLevelsGained = GetNumLevelsGainedFromSteps(daycare, slot);
+    GetBoxMonNick(&daycare->mons[slot], gStringVar1);
+    ConvertIntToDecimalStringN(gStringVar2, numLevelsGained, STR_CONV_MODE_LEFT_ALIGN, 2);
+    return numLevelsGained;
 }
 
-static u16 sub_8041728(struct DayCareData *dayCareData, u8 slot)
+static u16 GetDaycareCostForSelectedMon(struct DayCare *daycare, u8 slot)
 {
     u16 cost;
 
-    u8 levelDelta = sub_80416A0(dayCareData, slot);
-    GetBoxMonNick(&dayCareData->mons[slot], gStringVar1);
-    cost = 100 + 100 * levelDelta;
+    u8 numLevelsGained = GetNumLevelsGainedFromSteps(daycare, slot);
+    GetBoxMonNick(&daycare->mons[slot], gStringVar1);
+    cost = 100 + 100 * numLevelsGained;
     ConvertIntToDecimalStringN(gStringVar2, cost, STR_CONV_MODE_LEFT_ALIGN, 5);
     return cost;
 }
 
-void sub_8041770(void)
+void GetDaycareCost(void)
 {
-    gSpecialVar_0x8005 = sub_8041728(&gSaveBlock1.daycareData, gSpecialVar_0x8004);
+    gSpecialVar_0x8005 = GetDaycareCostForSelectedMon(&gSaveBlock1.daycare, gSpecialVar_0x8004);
 }
 
-void sub_8041790(u16 i)
+void Debug_AddDaycareSteps(u16 numSteps)
 {
-    gSaveBlock1.daycareData.misc.countersEtc.steps[0] += i;
-    gSaveBlock1.daycareData.misc.countersEtc.steps[1] += i;
+    gSaveBlock1.daycare.misc.countersEtc.steps[0] += numSteps;
+    gSaveBlock1.daycare.misc.countersEtc.steps[1] += numSteps;
 }
 
-u8 sub_80417B8(void)
+u8 GetNumLevelsGainedFromDaycare(void)
 {
-    if (GetBoxMonData(&gSaveBlock1.daycareData.mons[gSpecialVar_0x8004], MON_DATA_SPECIES) != 0)
-        return sub_80416E8(&gSaveBlock1.daycareData, gSpecialVar_0x8004);
+    if (GetBoxMonData(&gSaveBlock1.daycare.mons[gSpecialVar_0x8004], MON_DATA_SPECIES) != 0)
+        return GetNumLevelsGainedForDaycareSlot(&gSaveBlock1.daycare, gSpecialVar_0x8004);
+
     return 0;
 }
 
-static void sub_80417F4(struct DayCareMail *mail)
+static void ClearDaycareMail(struct DayCareMail *mail)
 {
-    u8 zero;
     u8 *names;
     u8 *names2;
-    int i;
-    zero = 0;
-    for (i = 7, names = mail->names + 7; i >= 0; i --)
+    s32 i;
+    u8 zero = 0;
+
+    for (i = 7, names = &mail->names[7]; i >= 0; i--)
+    {
         *names-- = zero;
-    names2 = mail->names + 8;
+    }
+
+    names2 = &mail->names[8];
     zero = 0;
-    names = mail->names + 18;
-    do *names-- = zero; while ((int)names >= (int)names2);
+    names = &mail->names[18];
+    do *names-- = zero; while ((s32)names >= (s32)names2);
     ClearMailStruct(&mail->message);
 }
 
-void unref_sub_8041824(struct DayCareData *dayCareData)
+void unref_sub_8041824(struct DayCare *daycare)
 {
     u8 slot;
-    for (slot = 0; slot < ARRAY_COUNT(dayCareData->mons); slot ++)
+    for (slot = 0; slot < ARRAY_COUNT(daycare->mons); slot++)
     {
-        ZeroBoxMonData(&dayCareData->mons[slot]);
-        dayCareData->misc.countersEtc.steps[slot] = 0;
-        sub_80417F4(&dayCareData->misc.mail[slot]);
+        ZeroBoxMonData(&daycare->mons[slot]);
+        daycare->misc.countersEtc.steps[slot] = 0;
+        ClearDaycareMail(&daycare->misc.mail[slot]);
     }
-    dayCareData->misc.countersEtc.personalityLo = 0;
-    dayCareData->misc.countersEtc.unk_11a = 0;
+
+    daycare->misc.countersEtc.pendingEggPersonality = 0;
+    daycare->misc.countersEtc.eggCycleStepsRemaining = 0;
 }
 
-u16 sub_8041870(u16 species)
+// Determines what the species of an Egg would be based on the given species.
+// It determines this by working backwards through the evolution chain of the
+// given species.
+u16 GetEggSpecies(u16 species)
 {
     int i, j, k;
     bool8 found;
-    for (i = 0; i < 5; i ++)
+
+    // Working backwards up to 5 times seems arbitrary, since the maximum number
+    // of times would only be 3 for 3-stage evolutions.
+    for (i = 0; i < 5; i++)
     {
         found = FALSE;
-        for (j = 1; j < NUM_SPECIES; j ++)
+        for (j = 1; j < NUM_SPECIES; j++)
         {
-            for (k = 0; k < 5; k ++)
+            for (k = 0; k < 5; k++)
             {
                 if (gEvolutionTable[j].evolutions[k].targetSpecies == species)
                 {
@@ -312,92 +348,118 @@ u16 sub_8041870(u16 species)
                     break;
                 }
             }
+
             if (found)
                 break;
         }
-        if (j == 412)
+
+        if (j == NUM_SPECIES)
             break;
     }
+
     return species;
 }
 
-static void sub_80418F0(struct DayCareData *dayCareData)
+static void _TriggerPendingDaycareEgg(struct DayCare *daycare)
 {
-    dayCareData->misc.countersEtc.personalityLo = (Random() % 0xfffe) + 1;
-    FlagSet(0x86);
+    daycare->misc.countersEtc.pendingEggPersonality = (Random() % 0xfffe) + 1;
+    FlagSet(FLAG_PENDING_DAYCARE_EGG);
 }
 
-static void sub_804191C(struct DayCareData *dayCareData)
+static void _TriggerPendingDaycareMaleEgg(struct DayCare *daycare)
 {
-    dayCareData->misc.countersEtc.personalityLo = Random() | 0x8000;
-    FlagSet(0x86);
+    daycare->misc.countersEtc.pendingEggPersonality = Random() | 0x8000;
+    FlagSet(FLAG_PENDING_DAYCARE_EGG);
 }
 
-void sub_8041940(void)
+void TriggerPendingDaycareEgg(void)
 {
-    sub_80418F0(&gSaveBlock1.daycareData);
+    _TriggerPendingDaycareEgg(&gSaveBlock1.daycare);
 }
 
-void sub_8041950(void)
+void TriggerPendingDaycareMaleEgg(void)
 {
-    sub_804191C(&gSaveBlock1.daycareData);
+    _TriggerPendingDaycareMaleEgg(&gSaveBlock1.daycare);
 }
 
-static void sub_8041960(u8 *data, u8 idx)
+// Removes the selected index from the given IV list and shifts the remaining
+// elements to the left.
+static void RemoveIVIndexFromList(u8 *ivs, u8 selectedIv)
 {
-    int i, j;
-    u8 temp[6];
-    data[idx] = 0xff;
-    for (i = 0; i < 6; i ++)
-        temp[i] = data[i];
+    s32 i, j;
+    u8 temp[NUM_STATS];
+
+    ivs[selectedIv] = 0xff;
+    for (i = 0; i < NUM_STATS; i++)
+    {
+        temp[i] = ivs[i];
+    }
+
     j = 0;
-    for (i = 0; i < 6; i ++)
+    for (i = 0; i < NUM_STATS; i++)
+    {
         if (temp[i] != 0xff)
-            data[j++] = temp[i];
+            ivs[j++] = temp[i];
+    }
 }
 
-static void InheritIVs(struct Pokemon *egg, struct DayCareData *dayCareData)
+static void InheritIVs(struct Pokemon *egg, struct DayCare *daycare)
 {
     u8 i;
     u8 selectedIvs[3];
-    u8 allIvs[6];
-    u8 whichParent[3];
+    u8 availableIVs[NUM_STATS];
+    u8 whichParent[ARRAY_COUNT(selectedIvs)];
     u8 iv;
-    for (i = 0; i < 6; i ++)
-        allIvs[i] = i;
-    for (i = 0; i < 3; i ++)
+
+    // Initialize a list of IV indices.
+    for (i = 0; i < NUM_STATS; i++)
     {
-        selectedIvs[i] = allIvs[Random() % (6 - i)];
-        sub_8041960(allIvs, selectedIvs[i]);
+        availableIVs[i] = i;
     }
-    for (i = 0; i < 3; i ++)
+
+    // Select the 3 IVs that will be inherited.
+    for (i = 0; i < ARRAY_COUNT(selectedIvs); i++)
+    {
+        // Randomly pick an IV from the available list.
+        selectedIvs[i] = availableIVs[Random() % (NUM_STATS - i)];
+
+        // Remove the selected IV index from the available IV indicies.
+        RemoveIVIndexFromList(availableIVs, selectedIvs[i]);
+    }
+
+    // Determine which parent each of the selected IVs should inherit from.
+    for (i = 0; i < ARRAY_COUNT(selectedIvs); i++)
+    {
         whichParent[i] = Random() % 2;
-    for (i = 0; i < 3; i ++)
+    }
+
+    // Set each of inherited IVs on the egg mon.
+    for (i = 0; i < ARRAY_COUNT(selectedIvs); i++)
     {
         switch (selectedIvs[i])
         {
             case 0:
-                iv = GetBoxMonData(&dayCareData->mons[whichParent[i]], MON_DATA_HP_IV);
+                iv = GetBoxMonData(&daycare->mons[whichParent[i]], MON_DATA_HP_IV);
                 SetMonData(egg, MON_DATA_HP_IV, &iv);
                 break;
             case 1:
-                iv = GetBoxMonData(&dayCareData->mons[whichParent[i]], MON_DATA_ATK_IV);
+                iv = GetBoxMonData(&daycare->mons[whichParent[i]], MON_DATA_ATK_IV);
                 SetMonData(egg, MON_DATA_ATK_IV, &iv);
                 break;
             case 2:
-                iv = GetBoxMonData(&dayCareData->mons[whichParent[i]], MON_DATA_DEF_IV);
+                iv = GetBoxMonData(&daycare->mons[whichParent[i]], MON_DATA_DEF_IV);
                 SetMonData(egg, MON_DATA_DEF_IV, &iv);
                 break;
             case 3:
-                iv = GetBoxMonData(&dayCareData->mons[whichParent[i]], MON_DATA_SPEED_IV);
+                iv = GetBoxMonData(&daycare->mons[whichParent[i]], MON_DATA_SPEED_IV);
                 SetMonData(egg, MON_DATA_SPEED_IV, &iv);
                 break;
             case 4:
-                iv = GetBoxMonData(&dayCareData->mons[whichParent[i]], MON_DATA_SPATK_IV);
+                iv = GetBoxMonData(&daycare->mons[whichParent[i]], MON_DATA_SPATK_IV);
                 SetMonData(egg, MON_DATA_SPATK_IV, &iv);
                 break;
             case 5:
-                iv = GetBoxMonData(&dayCareData->mons[whichParent[i]], MON_DATA_SPDEF_IV);
+                iv = GetBoxMonData(&daycare->mons[whichParent[i]], MON_DATA_SPDEF_IV);
                 SetMonData(egg, MON_DATA_SPDEF_IV, &iv);
                 break;
         }
@@ -407,17 +469,19 @@ static void InheritIVs(struct Pokemon *egg, struct DayCareData *dayCareData)
 #ifdef NONMATCHING
 static
 #endif
-u8 pokemon_get_eggmoves(struct Pokemon *pokemon, u16 *eggMoves)
+// Counts the number of egg moves a pokemon learns and stores the moves in
+// the given array.
+u8 GetEggMoves(struct Pokemon *pokemon, u16 *eggMoves)
 {
     u16 eggMoveIdx;
-    u16 numMovesFound;
+    u16 numEggMoves;
     u16 species;
     u16 i;
 
-    numMovesFound = 0;
+    numEggMoves = 0;
     eggMoveIdx = 0;
     species = GetMonData(pokemon, MON_DATA_SPECIES);
-    for (i = 0; i < ARRAY_COUNT(gEggMoves) - 1; i ++)
+    for (i = 0; i < ARRAY_COUNT(gEggMoves) - 1; i++)
     {
         if (gEggMoves[i] == species + EGG_MOVES_SPECIES_OFFSET)
         {
@@ -425,57 +489,61 @@ u8 pokemon_get_eggmoves(struct Pokemon *pokemon, u16 *eggMoves)
             break;
         }
     }
-    for (i = 0; i < 10; i ++)
+
+    for (i = 0; i < 10; i++)
     {
         if (gEggMoves[eggMoveIdx + i] > EGG_MOVES_SPECIES_OFFSET)
         {
+            // TODO: the curly braces around this if statement are required for a matching build.
             break;
         }
+
         eggMoves[i] = gEggMoves[eggMoveIdx + i];
-        numMovesFound++;
+        numEggMoves++;
     }
-    return numMovesFound;
+
+    return numEggMoves;
 }
 
 #ifdef NONMATCHING
-
-void daycare_build_child_moveset(struct Pokemon *egg, struct BoxPokemon *dad, struct BoxPokemon *mom)
+void BuildEggMoveset(struct Pokemon *egg, struct BoxPokemon *father, struct BoxPokemon *mother)
 {
     u16 numSharedParentMoves;
     u8 numLevelUpMoves;
-    u8 numEggMoves;
+    u16 numEggMoves;
     u16 i, j;
 
     numSharedParentMoves = 0;
-    for (i = 0; i < 4; i ++)
+    for (i = 0; i < 4; i++)
     {
-        gUnknown_03000500[i] = 0;
-        gUnknown_030004D8[i] = 0;
-        gUnknown_030004E0[i] = 0;
+        gHatchedEggMotherMoves[i] = 0;
+        gHatchedEggFatherMoves[i] = 0;
+        gHatchedEggFinalMoves[i] = 0;
     }
-    for (i = 0; i < 10; i ++)
-        gUnknown_030004E8[i] = 0;
-    for (i = 0; i < 50; i ++)
-        gUnknown_03000470[i] = 0;
+    for (i = 0; i < 10; i++)
+        gHatchedEggEggMoves[i] = 0;
+    for (i = 0; i < 50; i++)
+        gHatchedEggLevelUpMoves[i] = 0;
 
-    numLevelUpMoves = GetLevelUpMovesBySpecies(GetMonData(egg, MON_DATA_SPECIES), gUnknown_03000470);
-    for (i = 0; i < 4; i ++)
+    numLevelUpMoves = GetLevelUpMovesBySpecies(GetMonData(egg, MON_DATA_SPECIES), gHatchedEggLevelUpMoves);
+    for (i = 0; i < 4; i++)
     {
-        gUnknown_030004D8[i] = GetBoxMonData(dad, MON_DATA_MOVE1 + i);
-        gUnknown_03000500[i] = GetBoxMonData(mom, MON_DATA_MOVE1 + i);
+        gHatchedEggFatherMoves[i] = GetBoxMonData(father, MON_DATA_MOVE1 + i);
+        gHatchedEggMotherMoves[i] = GetBoxMonData(mother, MON_DATA_MOVE1 + i);
     }
-    numEggMoves = pokemon_get_eggmoves(egg, gUnknown_030004E8);
 
-    for (i = 0; i < 4; i ++)
+    numEggMoves = GetEggMoves(egg, gHatchedEggEggMoves);
+
+    for (i = 0; i < 4; i++)
     {
-        if (gUnknown_030004D8[i] != MOVE_NONE)
+        if (gHatchedEggFatherMoves[i] != MOVE_NONE)
         {
-            for (j = 0; j < numEggMoves; j ++)
+            for (j = 0; j < (u32)numEggMoves; j++)
             {
-                if (gUnknown_030004D8[i] == gUnknown_030004E8[j])
+                if (gHatchedEggFatherMoves[i] == gHatchedEggEggMoves[j])
                 {
-                    if (GiveMoveToMon(egg, gUnknown_030004D8[i]) == 0xffff)
-                        DeleteFirstMoveAndGiveMoveToMon(egg, gUnknown_030004D8[i]);
+                    if (GiveMoveToMon(egg, gHatchedEggFatherMoves[i]) == 0xffff)
+                        DeleteFirstMoveAndGiveMoveToMon(egg, gHatchedEggFatherMoves[i]);
                     break;
                 }
             }
@@ -483,40 +551,41 @@ void daycare_build_child_moveset(struct Pokemon *egg, struct BoxPokemon *dad, st
         else
             break;
     }
-    for (i = 0; i < 4; i ++)
+    for (i = 0; i < 4; i++)
     {
-        if (gUnknown_030004D8[i] != MOVE_NONE)
+        if (gHatchedEggFatherMoves[i] != MOVE_NONE)
         {
-            for (j = 0; j < 50 + 8; j ++)
+            for (j = 0; j < NUM_TECHNICAL_MACHINES + NUM_HIDDEN_MACHINES; j++)
             {
-                if (gUnknown_030004D8[i] == ItemIdToBattleMoveId(ITEM_TM01 + j) && CanMonLearnTMHM(egg, j))
+                if (gHatchedEggFatherMoves[i] == ItemIdToBattleMoveId(ITEM_TM01 + j) && CanMonLearnTMHM(egg, j))
                 {
-                    if (GiveMoveToMon(egg, gUnknown_030004D8[i]) == 0xffff)
-                        DeleteFirstMoveAndGiveMoveToMon(egg, gUnknown_030004D8[i]);
+                    if (GiveMoveToMon(egg, gHatchedEggFatherMoves[i]) == 0xffff)
+                        DeleteFirstMoveAndGiveMoveToMon(egg, gHatchedEggFatherMoves[i]);
                 }
             }
         }
     }
-    for (i = 0; i < 4; i ++)
+    for (i = 0; i < 4; i++)
     {
-        if (gUnknown_030004D8[i] == MOVE_NONE)
+        if (gHatchedEggFatherMoves[i] == MOVE_NONE)
             break;
-        for (j = 0; j < 4; j ++)
+        for (j = 0; j < 4; j++)
         {
-            if (gUnknown_030004D8[i] == gUnknown_03000500[j] && gUnknown_030004D8[i] != MOVE_NONE)
-                gUnknown_030004E0[numSharedParentMoves++] = gUnknown_030004D8[i];
+            if (gHatchedEggFatherMoves[i] == gHatchedEggMotherMoves[j] && gHatchedEggFatherMoves[i] != MOVE_NONE)
+                gHatchedEggFinalMoves[numSharedParentMoves++] = gHatchedEggFatherMoves[i];
         }
     }
-    for (i = 0; i < 4; i ++)
+
+    for (i = 0; i < 4; i++)
     {
-        if (gUnknown_030004E0[i] == MOVE_NONE)
+        if (gHatchedEggFinalMoves[i] == MOVE_NONE)
             break;
-        for (j = 0; j < numLevelUpMoves; j ++)
+        for (j = 0; j < numLevelUpMoves; j++)
         {
-            if (gUnknown_03000470[j] != MOVE_NONE && gUnknown_030004E0[i] == gUnknown_03000470[j])
+            if (gHatchedEggLevelUpMoves[j] != MOVE_NONE && gHatchedEggFinalMoves[i] == gHatchedEggLevelUpMoves[j])
             {
-                if (GiveMoveToMon(egg, gUnknown_030004E0[i]) == 0xffff)
-                    DeleteFirstMoveAndGiveMoveToMon(egg, gUnknown_030004E0[i]);
+                if (GiveMoveToMon(egg, gHatchedEggFinalMoves[i]) == 0xffff)
+                    DeleteFirstMoveAndGiveMoveToMon(egg, gHatchedEggFinalMoves[i]);
                 break;
             }
         }
@@ -524,7 +593,7 @@ void daycare_build_child_moveset(struct Pokemon *egg, struct BoxPokemon *dad, st
 }
 #else
 __attribute__((naked))
-void daycare_build_child_moveset(struct Pokemon *egg, struct BoxPokemon *dad, struct BoxPokemon *mom)
+void BuildEggMoveset(struct Pokemon *egg, struct BoxPokemon *father, struct BoxPokemon *mother)
 {
     asm_unified("\tpush {r4-r7,lr}\n"
                     "\tmov r7, r10\n"
@@ -538,10 +607,10 @@ void daycare_build_child_moveset(struct Pokemon *egg, struct BoxPokemon *dad, st
                     "\tmovs r0, 0\n"
                     "\tstr r0, [sp]\n"
                     "\tmovs r6, 0\n"
-                    "\tldr r5, _08041CC8 @ =gUnknown_03000500\n"
+                    "\tldr r5, _08041CC8 @ =gHatchedEggMotherMoves\n"
                     "\tmovs r2, 0\n"
-                    "\tldr r4, _08041CCC @ =gUnknown_030004D8\n"
-                    "\tldr r3, _08041CD0 @ =gUnknown_030004E0\n"
+                    "\tldr r4, _08041CCC @ =gHatchedEggFatherMoves\n"
+                    "\tldr r3, _08041CD0 @ =gHatchedEggFinalMoves\n"
                     "_08041BE4:\n"
                     "\tlsls r1, r6, 1\n"
                     "\tadds r0, r1, r5\n"
@@ -556,7 +625,7 @@ void daycare_build_child_moveset(struct Pokemon *egg, struct BoxPokemon *dad, st
                     "\tcmp r6, 0x3\n"
                     "\tbls _08041BE4\n"
                     "\tmovs r6, 0\n"
-                    "\tldr r2, _08041CD4 @ =gUnknown_030004E8\n"
+                    "\tldr r2, _08041CD4 @ =gHatchedEggEggMoves\n"
                     "\tmovs r1, 0\n"
                     "_08041C02:\n"
                     "\tlsls r0, r6, 1\n"
@@ -568,7 +637,7 @@ void daycare_build_child_moveset(struct Pokemon *egg, struct BoxPokemon *dad, st
                     "\tcmp r6, 0x9\n"
                     "\tbls _08041C02\n"
                     "\tmovs r6, 0\n"
-                    "\tldr r2, _08041CD8 @ =gUnknown_03000470\n"
+                    "\tldr r2, _08041CD8 @ =gHatchedEggLevelUpMoves\n"
                     "\tmovs r1, 0\n"
                     "_08041C18:\n"
                     "\tlsls r0, r6, 1\n"
@@ -584,13 +653,13 @@ void daycare_build_child_moveset(struct Pokemon *egg, struct BoxPokemon *dad, st
                     "\tbl GetMonData\n"
                     "\tlsls r0, 16\n"
                     "\tlsrs r0, 16\n"
-                    "\tldr r1, _08041CD8 @ =gUnknown_03000470\n"
+                    "\tldr r1, _08041CD8 @ =gHatchedEggLevelUpMoves\n"
                     "\tbl GetLevelUpMovesBySpecies\n"
                     "\tlsls r0, 24\n"
                     "\tlsrs r0, 24\n"
                     "\tstr r0, [sp, 0x4]\n"
                     "\tmovs r6, 0\n"
-                    "\tldr r1, _08041CCC @ =gUnknown_030004D8\n"
+                    "\tldr r1, _08041CCC @ =gHatchedEggFatherMoves\n"
                     "\tmov r8, r1\n"
                     "_08041C46:\n"
                     "\tadds r5, r6, 0\n"
@@ -605,7 +674,7 @@ void daycare_build_child_moveset(struct Pokemon *egg, struct BoxPokemon *dad, st
                     "\tmov r0, r9\n"
                     "\tadds r1, r5, 0\n"
                     "\tbl GetBoxMonData\n"
-                    "\tldr r1, _08041CC8 @ =gUnknown_03000500\n"
+                    "\tldr r1, _08041CC8 @ =gHatchedEggMotherMoves\n"
                     "\tadds r4, r1\n"
                     "\tstrh r0, [r4]\n"
                     "\tadds r0, r6, 0x1\n"
@@ -613,15 +682,15 @@ void daycare_build_child_moveset(struct Pokemon *egg, struct BoxPokemon *dad, st
                     "\tlsrs r6, r0, 16\n"
                     "\tcmp r6, 0x3\n"
                     "\tbls _08041C46\n"
-                    "\tldr r1, _08041CD4 @ =gUnknown_030004E8\n"
+                    "\tldr r1, _08041CD4 @ =gHatchedEggEggMoves\n"
                     "\tadds r0, r7, 0\n"
-                    "\tbl pokemon_get_eggmoves\n"
+                    "\tbl GetEggMoves\n"
                     "\tlsls r0, 24\n"
                     "\tlsrs r0, 24\n"
                     "\tmov r8, r0\n"
                     "\tmovs r6, 0\n"
                     "_08041C82:\n"
-                    "\tldr r0, _08041CCC @ =gUnknown_030004D8\n"
+                    "\tldr r0, _08041CCC @ =gHatchedEggFatherMoves\n"
                     "\tlsls r1, r6, 1\n"
                     "\tadds r2, r1, r0\n"
                     "\tldrh r1, [r2]\n"
@@ -634,7 +703,7 @@ void daycare_build_child_moveset(struct Pokemon *egg, struct BoxPokemon *dad, st
                     "\tadds r4, r2, 0\n"
                     "\tldr r2, _08041CDC @ =0x0000ffff\n"
                     "_08041C9A:\n"
-                    "\tldr r0, _08041CD4 @ =gUnknown_030004E8\n"
+                    "\tldr r0, _08041CD4 @ =gHatchedEggEggMoves\n"
                     "\tlsls r1, r5, 1\n"
                     "\tadds r1, r0\n"
                     "\tldrh r0, [r4]\n"
@@ -655,11 +724,11 @@ void daycare_build_child_moveset(struct Pokemon *egg, struct BoxPokemon *dad, st
                     "\tbl DeleteFirstMoveAndGiveMoveToMon\n"
                     "\tb _08041CEA\n"
                     "\t.align 2, 0\n"
-                    "_08041CC8: .4byte gUnknown_03000500\n"
-                    "_08041CCC: .4byte gUnknown_030004D8\n"
-                    "_08041CD0: .4byte gUnknown_030004E0\n"
-                    "_08041CD4: .4byte gUnknown_030004E8\n"
-                    "_08041CD8: .4byte gUnknown_03000470\n"
+                    "_08041CC8: .4byte gHatchedEggMotherMoves\n"
+                    "_08041CCC: .4byte gHatchedEggFatherMoves\n"
+                    "_08041CD0: .4byte gHatchedEggFinalMoves\n"
+                    "_08041CD4: .4byte gHatchedEggEggMoves\n"
+                    "_08041CD8: .4byte gHatchedEggLevelUpMoves\n"
                     "_08041CDC: .4byte 0x0000ffff\n"
                     "_08041CE0:\n"
                     "\tadds r0, r5, 0x1\n"
@@ -671,7 +740,7 @@ void daycare_build_child_moveset(struct Pokemon *egg, struct BoxPokemon *dad, st
                     "\tadds r0, r6, 0x1\n"
                     "\tlsls r0, 16\n"
                     "\tlsrs r6, r0, 16\n"
-                    "\tldr r3, _08041E14 @ =gUnknown_030004D8\n"
+                    "\tldr r3, _08041E14 @ =gHatchedEggFatherMoves\n"
                     "\tmov r9, r3\n"
                     "\tcmp r6, 0x3\n"
                     "\tbls _08041C82\n"
@@ -688,7 +757,7 @@ void daycare_build_child_moveset(struct Pokemon *egg, struct BoxPokemon *dad, st
                     "\tcmp r1, 0\n"
                     "\tbeq _08041D5C\n"
                     "\tmovs r5, 0\n"
-                    "\tldr r0, _08041E14 @ =gUnknown_030004D8\n"
+                    "\tldr r0, _08041E14 @ =gHatchedEggFatherMoves\n"
                     "\tadds r4, r2, r0\n"
                     "\tldr r6, _08041E18 @ =0x0000ffff\n"
                     "\tmov r9, r0\n"
@@ -734,12 +803,12 @@ void daycare_build_child_moveset(struct Pokemon *egg, struct BoxPokemon *dad, st
                     "\tmovs r6, 0\n"
                     "\tmov r2, r9\n"
                     "\tldrh r0, [r2]\n"
-                    "\tldr r3, _08041E20 @ =gUnknown_030004E0\n"
+                    "\tldr r3, _08041E20 @ =gHatchedEggFinalMoves\n"
                     "\tmov r10, r3\n"
                     "\tcmp r0, 0\n"
                     "\tbeq _08041DC6\n"
                     "\tmov r4, r9\n"
-                    "\tldr r0, _08041E24 @ =gUnknown_03000500\n"
+                    "\tldr r0, _08041E24 @ =gHatchedEggMotherMoves\n"
                     "\tmov r9, r0\n"
                     "\tmov r12, r10\n"
                     "_08041D7C:\n"
@@ -797,7 +866,7 @@ void daycare_build_child_moveset(struct Pokemon *egg, struct BoxPokemon *dad, st
                     "\tbcs _08041E38\n"
                     "\tldr r2, _08041E18 @ =0x0000ffff\n"
                     "_08041DDE:\n"
-                    "\tldr r1, _08041E28 @ =gUnknown_03000470\n"
+                    "\tldr r1, _08041E28 @ =gHatchedEggLevelUpMoves\n"
                     "\tlsls r0, r5, 1\n"
                     "\tadds r0, r1\n"
                     "\tldrh r1, [r0]\n"
@@ -823,12 +892,12 @@ void daycare_build_child_moveset(struct Pokemon *egg, struct BoxPokemon *dad, st
                     "\tbl DeleteFirstMoveAndGiveMoveToMon\n"
                     "\tb _08041E38\n"
                     "\t.align 2, 0\n"
-                    "_08041E14: .4byte gUnknown_030004D8\n"
+                    "_08041E14: .4byte gHatchedEggFatherMoves\n"
                     "_08041E18: .4byte 0x0000ffff\n"
                     "_08041E1C: .4byte 0x00000121\n"
-                    "_08041E20: .4byte gUnknown_030004E0\n"
-                    "_08041E24: .4byte gUnknown_03000500\n"
-                    "_08041E28: .4byte gUnknown_03000470\n"
+                    "_08041E20: .4byte gHatchedEggFinalMoves\n"
+                    "_08041E24: .4byte gHatchedEggMotherMoves\n"
+                    "_08041E28: .4byte gHatchedEggLevelUpMoves\n"
                     "_08041E2C:\n"
                     "\tadds r0, r5, 0x1\n"
                     "\tlsls r0, 16\n"
@@ -842,7 +911,7 @@ void daycare_build_child_moveset(struct Pokemon *egg, struct BoxPokemon *dad, st
                     "\tlsrs r6, r0, 16\n"
                     "\tcmp r6, 0x3\n"
                     "\tbhi _08041E50\n"
-                    "\tldr r0, _08041E60 @ =gUnknown_030004E0\n"
+                    "\tldr r0, _08041E60 @ =gHatchedEggFinalMoves\n"
                     "\tlsls r1, r6, 1\n"
                     "\tadds r1, r0\n"
                     "\tldrh r1, [r1]\n"
@@ -859,166 +928,178 @@ void daycare_build_child_moveset(struct Pokemon *egg, struct BoxPokemon *dad, st
                     "\tpop {r0}\n"
                     "\tbx r0\n"
                     "\t.align 2, 0\n"
-                    "_08041E60: .4byte gUnknown_030004E0");
+                    "_08041E60: .4byte gHatchedEggFinalMoves");
 }
 #endif
 
-static void RemoveEggFromDayCare(struct DayCareData *dayCareData)
+static void RemoveEggFromDayCare(struct DayCare *daycare)
 {
-    dayCareData->misc.countersEtc.personalityLo = 0;
-    dayCareData->misc.countersEtc.unk_11a = 0;
+    daycare->misc.countersEtc.pendingEggPersonality = 0;
+    daycare->misc.countersEtc.eggCycleStepsRemaining = 0;
 }
 
-void sub_8041E7C(void)
+void RejectEggFromDayCare(void)
 {
-    RemoveEggFromDayCare(&gSaveBlock1.daycareData);
+    RemoveEggFromDayCare(&gSaveBlock1.daycare);
 }
 
-static void incense_effects(u16 *species, struct DayCareData *dayCareData)
+static void AlterEggSpeciesWithIncenseItem(u16 *species, struct DayCare *daycare)
 {
-    u16 momItem, dadItem;
+    u16 motherItem, fatherItem;
     if (*species == SPECIES_WYNAUT || *species == SPECIES_AZURILL)
     {
-        momItem = GetBoxMonData(&dayCareData->mons[0], MON_DATA_HELD_ITEM);
-        dadItem = GetBoxMonData(&dayCareData->mons[1], MON_DATA_HELD_ITEM);
-        if (*species == SPECIES_WYNAUT && momItem != ITEM_LAX_INCENSE && dadItem != ITEM_LAX_INCENSE)
+        motherItem = GetBoxMonData(&daycare->mons[0], MON_DATA_HELD_ITEM);
+        fatherItem = GetBoxMonData(&daycare->mons[1], MON_DATA_HELD_ITEM);
+        if (*species == SPECIES_WYNAUT && motherItem != ITEM_LAX_INCENSE && fatherItem != ITEM_LAX_INCENSE)
         {
             *species = SPECIES_WOBBUFFET;
         }
-        if (*species == SPECIES_AZURILL && momItem != ITEM_SEA_INCENSE && dadItem != ITEM_SEA_INCENSE)
+
+        if (*species == SPECIES_AZURILL && motherItem != ITEM_SEA_INCENSE && fatherItem != ITEM_SEA_INCENSE)
         {
             *species = SPECIES_MARILL;
         }
     }
 }
 
-static u16 sub_8041EEC(struct DayCareData *dayCareData, u8 *a1) // inherit_species_from_mom
+static u16 DetermineEggSpeciesAndParentSlots(struct DayCare *daycare, u8 *parentSlots)
 {
     u16 i;
     u16 species[2];
     u16 eggSpecies;
-    u8 buffer;
-    for (i=0; i<2; i++)
+
+    // Determine which of the daycare mons is the mother and father of the egg.
+    // The 0th index of the parentSlots array is considered the mother slot, and the
+    // 1st index is the father slot.
+    for (i = 0; i < 2; i++)
     {
-        species[i] = GetBoxMonData(&dayCareData->mons[i], MON_DATA_SPECIES);
+        species[i] = GetBoxMonData(&daycare->mons[i], MON_DATA_SPECIES);
         if (species[i] == SPECIES_DITTO)
         {
-            a1[0] = i ^ 1;
-            a1[1] = i;
+            parentSlots[0] = i ^ 1;
+            parentSlots[1] = i;
         }
-        else if (GetBoxMonGender(&dayCareData->mons[i]) == MON_FEMALE)
+        else if (GetBoxMonGender(&daycare->mons[i]) == MON_FEMALE)
         {
-            a1[0] = i;
-            a1[1] = i ^ 1;
+            parentSlots[0] = i;
+            parentSlots[1] = i ^ 1;
         }
     }
-    eggSpecies = sub_8041870(species[a1[0]]);
-    if (eggSpecies == SPECIES_NIDORAN_F && dayCareData->misc.countersEtc.personalityLo & 0x8000)
+
+    eggSpecies = GetEggSpecies(species[parentSlots[0]]);
+    if (eggSpecies == SPECIES_NIDORAN_F && daycare->misc.countersEtc.pendingEggPersonality & 0x8000)
     {
         eggSpecies = SPECIES_NIDORAN_M;
     }
-    if (eggSpecies == SPECIES_ILLUMISE && dayCareData->misc.countersEtc.personalityLo & 0x8000)
+    if (eggSpecies == SPECIES_ILLUMISE && daycare->misc.countersEtc.pendingEggPersonality & 0x8000)
     {
         eggSpecies = SPECIES_VOLBEAT;
     }
-    if (species[a1[1]] == SPECIES_DITTO && GetBoxMonGender(&dayCareData->mons[a1[0]]) != MON_FEMALE)
+
+    // Make Ditto the "mother" slot if the other daycare mon is male.
+    if (species[parentSlots[1]] == SPECIES_DITTO && GetBoxMonGender(&daycare->mons[parentSlots[0]]) != MON_FEMALE)
     {
-        buffer = a1[1];
-        a1[1] = a1[0];
-        a1[0] = buffer;
+        u8 temp = parentSlots[1];
+        parentSlots[1] = parentSlots[0];
+        parentSlots[0] = temp;
     }
+
     return eggSpecies;
 }
 
-static void sub_8041FC4(struct DayCareData *dayCareData) // give_egg
+static void _GiveEggFromDaycare(struct DayCare *daycare) // give_egg
 {
     struct Pokemon egg;
     u16 species;
-    u8 parents[2];
+    u8 parentSlots[2]; // 0th index is "mother" daycare slot, 1st is "father"
     u8 isEgg;
-    species = sub_8041EEC(dayCareData, parents);
-    incense_effects(&species, dayCareData);
-    sub_80420FC(&egg, species, dayCareData);
-    InheritIVs(&egg, dayCareData);
-    daycare_build_child_moveset(&egg, &dayCareData->mons[parents[1]], &dayCareData->mons[parents[0]]);
+
+    species = DetermineEggSpeciesAndParentSlots(daycare, parentSlots);
+    AlterEggSpeciesWithIncenseItem(&species, daycare);
+    SetInitialEggData(&egg, species, daycare);
+    InheritIVs(&egg, daycare);
+    BuildEggMoveset(&egg, &daycare->mons[parentSlots[1]], &daycare->mons[parentSlots[0]]);
     isEgg = TRUE;
     SetMonData(&egg, MON_DATA_IS_EGG, &isEgg);
     gPlayerParty[5] = egg;
     party_compaction();
     CalculatePlayerPartyCount();
-    RemoveEggFromDayCare(dayCareData);
+    RemoveEggFromDayCare(daycare);
 }
 
 
-void sub_8042044(struct Pokemon *mon, u16 species, u8 overwriteMetLocation) // scr_create_egg
+void CreateEgg(struct Pokemon *mon, u16 species, bool8 setMetLocation)
 {
     u8 metLevel;
     u16 ball;
     u8 language;
     u8 metLocation;
     u8 isEgg;
+
     CreateMon(mon, species, 5, 0x20, FALSE, 0, FALSE, 0);
     metLevel = 0;
     ball = ITEM_POKE_BALL;
     language = LANGUAGE_JAPANESE;
     SetMonData(mon, MON_DATA_POKEBALL, &ball);
-    SetMonData(mon, MON_DATA_NICKNAME, gUnknown_08209AD4);
+    SetMonData(mon, MON_DATA_NICKNAME, sJapaneseEggNickname);
     SetMonData(mon, MON_DATA_FRIENDSHIP, &gBaseStats[species].eggCycles);
     SetMonData(mon, MON_DATA_MET_LEVEL, &metLevel);
     SetMonData(mon, MON_DATA_LANGUAGE, &language);
-    if (overwriteMetLocation)
+    if (setMetLocation)
     {
-        metLocation = 0xfd;
+        metLocation = 253; // hot springs; see PokemonSummaryScreen_PrintEggTrainerMemo
         SetMonData(mon, MON_DATA_MET_LOCATION, &metLocation);
     }
+
     isEgg = TRUE;
     SetMonData(mon, MON_DATA_IS_EGG, &isEgg);
 }
 
-static void sub_80420FC(struct Pokemon *mon, u16 species, struct DayCareData *dayCareData)
+static void SetInitialEggData(struct Pokemon *mon, u16 species, struct DayCare *daycare)
 {
     u32 personality;
     u16 ball;
     u8 metLevel;
     u8 language;
-    personality = dayCareData->misc.countersEtc.personalityLo | (Random() << 16);
+
+    personality = daycare->misc.countersEtc.pendingEggPersonality | (Random() << 16);
     CreateMon(mon, species, 5, 0x20, TRUE, personality, FALSE, 0);
     metLevel = 0;
     ball = ITEM_POKE_BALL;
     language = LANGUAGE_JAPANESE;
     SetMonData(mon, MON_DATA_POKEBALL, &ball);
-    SetMonData(mon, MON_DATA_NICKNAME, gUnknown_08209AD4);
+    SetMonData(mon, MON_DATA_NICKNAME, sJapaneseEggNickname);
     SetMonData(mon, MON_DATA_FRIENDSHIP, &gBaseStats[species].eggCycles);
     SetMonData(mon, MON_DATA_MET_LEVEL, &metLevel);
     SetMonData(mon, MON_DATA_LANGUAGE, &language);
 }
 
-void sp0B8_daycare(void)
+void GiveEggFromDaycare(void)
 {
-    sub_8041FC4(&gSaveBlock1.daycareData);
+    _GiveEggFromDaycare(&gSaveBlock1.daycare);
 }
 
 #ifdef NONMATCHING
-static bool8 sub_80421B0(struct DayCareData *dayCareData)
+static bool8 _ShouldEggHatch(struct DayCare *daycare)
 {
     struct BoxPokemon *parent;
     u32 i;
     int v0;
     int steps;
     v0 = 0;
-    for (i=0, parent=&dayCareData->mons[0]; i<2; parent++, i++)
+    for (i=0, parent=&daycare->mons[0]; i<2; parent++, i++)
     {
         if (GetBoxMonData(parent, MON_DATA_SANITY_BIT2, v0))
         {
-            dayCareData->misc.countersEtc.steps[i]++;
+            daycare->misc.countersEtc.steps[i]++;
             v0++;
         }
     }
-    if (dayCareData->misc.countersEtc.personalityLo == 0 && v0 == 2 && dayCareData->misc.extra.misc[4] == 0xff && daycare_relationship_score(dayCareData) > (u32)((u32)(Random() * 100) / 0xffff))
+    if (daycare->misc.countersEtc.pendingEggPersonality == 0 && v0 == 2 && daycare->misc.extra.misc[4] == 0xff && GetDaycareCompatibilityScore(daycare) > (u32)((u32)(Random() * 100) / 0xffff))
     {
-        sub_8041940();
+        TriggerPendingDaycareEgg();
     }
-    if ((++dayCareData->misc.countersEtc.unk_11a) == 0xff)
+    if ((++daycare->misc.countersEtc.eggCycleStepsRemaining) == 0xff)
     {
         for (i=0; i<gPlayerPartyCount; i++)
         {
@@ -1039,7 +1120,7 @@ static bool8 sub_80421B0(struct DayCareData *dayCareData)
 }
 #else
 __attribute__((naked))
-static bool8 sub_80421B0(struct DayCareData *dayCareData)
+static bool8 _ShouldEggHatch(struct DayCare *daycare)
 {
     asm_unified("\tpush {r4-r7,lr}\n"
                     "\tsub sp, 0x8\n"
@@ -1083,7 +1164,7 @@ static bool8 sub_80421B0(struct DayCareData *dayCareData)
                     "\tcmp r0, 0xFF\n"
                     "\tbne _08042226\n"
                     "\tadds r0, r7, 0\n"
-                    "\tbl daycare_relationship_score\n"
+                    "\tbl GetDaycareCompatibilityScore\n"
                     "\tadds r4, r0, 0\n"
                     "\tlsls r4, 24\n"
                     "\tlsrs r4, 24\n"
@@ -1096,7 +1177,7 @@ static bool8 sub_80421B0(struct DayCareData *dayCareData)
                     "\tbl __udivsi3\n"
                     "\tcmp r4, r0\n"
                     "\tbls _08042226\n"
-                    "\tbl sub_8041940\n"
+                    "\tbl TriggerPendingDaycareEgg\n"
                     "_08042226:\n"
                     "\tmovs r0, 0x8D\n"
                     "\tlsls r0, 1\n"
@@ -1162,68 +1243,81 @@ static bool8 sub_80421B0(struct DayCareData *dayCareData)
 }
 #endif
 
-bool8 sub_80422A0(void)
+bool8 ShouldEggHatch(void)
 {
-    return sub_80421B0(&gSaveBlock1.daycareData);
+    return _ShouldEggHatch(&gSaveBlock1.daycare);
 }
 
-static bool8 sub_80422B4(struct DayCareData *dayCareData)
+static bool8 IsEggPending(struct DayCare *daycare)
 {
-    return (u32)((-dayCareData->misc.countersEtc.personalityLo) | dayCareData->misc.countersEtc.personalityLo) >> 31;
+    return (u32)((-daycare->misc.countersEtc.pendingEggPersonality) | daycare->misc.countersEtc.pendingEggPersonality) >> 31;
 }
 
-static void sub_80422C4(struct DayCareData *dayCareData)
+static void _GetDaycareMonNicknames(struct DayCare *daycare)
 {
     u8 language;
-    if (GetBoxMonData(&dayCareData->mons[0], MON_DATA_SPECIES) != 0)
+    if (GetBoxMonData(&daycare->mons[0], MON_DATA_SPECIES) != 0)
     {
-        GetBoxMonNick(&dayCareData->mons[0], gStringVar1);
-        language = GetBoxMonData(&dayCareData->mons[0], MON_DATA_LANGUAGE);
-        GetBoxMonData(&dayCareData->mons[0], MON_DATA_OT_NAME, gStringVar3);
+        GetBoxMonNick(&daycare->mons[0], gStringVar1);
+        language = GetBoxMonData(&daycare->mons[0], MON_DATA_LANGUAGE);
+        GetBoxMonData(&daycare->mons[0], MON_DATA_OT_NAME, gStringVar3);
         ConvertInternationalString(gStringVar3, language);
     }
-    if (GetBoxMonData(&dayCareData->mons[1], MON_DATA_SPECIES) != 0)
+
+    if (GetBoxMonData(&daycare->mons[1], MON_DATA_SPECIES) != 0)
     {
-        GetBoxMonNick(&dayCareData->mons[1], gStringVar2);
+        GetBoxMonNick(&daycare->mons[1], gStringVar2);
     }
 }
 
-u16 sub_8042328(void)
+u16 GetSelectedDaycareMonNickname(void)
 {
     GetBoxMonNick(&gPlayerParty[gLastFieldPokeMenuOpened].box, gStringVar1);
     return GetBoxMonData(&gPlayerParty[gLastFieldPokeMenuOpened].box, MON_DATA_SPECIES);
 }
 
-void sp0B5_daycare(void)
+void GetDaycareMonNicknames(void)
 {
-    sub_80422C4(&gSaveBlock1.daycareData);
+    _GetDaycareMonNicknames(&gSaveBlock1.daycare);
 }
 
-u8 sp0B6_daycare(void)
+u8 GetDaycareState(void)
 {
-    u8 monCount;
-    if (sub_80422B4(&gSaveBlock1.daycareData))
+    // The daycare can be in 4 possible states:
+    //   0: default state--no deposited mons, no egg
+    //   1: there is an egg waiting for the player to pick it up
+    //   2: there is a single pokemon in the daycare
+    //   3: there are two pokemon in the daycare, no egg
+
+    u8 numMons;
+    if (IsEggPending(&gSaveBlock1.daycare))
     {
+        // There is an Egg waiting for the player.
         return 1;
     }
-    monCount = Daycare_CountPokemon(&gSaveBlock1.daycareData);
-    if (monCount != 0)
+
+    numMons = CountPokemonInDaycare(&gSaveBlock1.daycare);
+    if (numMons != 0)
     {
-        return monCount + 1;
+        return numMons + 1;
     }
+
     return 0;
 }
 
 #ifdef NONMATCHING
 static
 #endif
-bool8 sub_80423A8(u16 *a, u16 *b)
+bool8 EggGroupsOverlap(u16 *eggGroups1, u16 *eggGroups2)
 {
-    int i, j;
+    // Determine if the two given egg group lists contain any of the
+    // same egg groups.
+    s32 i, j;
     u16 *v0, *v1, v2;
-    for (i=0, v0=a; i<2; v0++, i++)
+
+    for (i = 0, v0 = eggGroups1; i < 2; v0++, i++)
     {
-        for (j=0, v2=*v0, v1=b; j<2; v1++, j++)
+        for (j = 0, v2 = *v0, v1 = eggGroups2; j < 2; v1++, j++)
         {
             if (v2 == *v1)
             {
@@ -1231,11 +1325,12 @@ bool8 sub_80423A8(u16 *a, u16 *b)
             }
         }
     }
+
     return FALSE;
 }
 
 #ifdef NONMATCHING
-static u8 daycare_relationship_score(struct DayCareData *dayCareData)
+static u8 GetDaycareCompatibilityScore(struct DayCare *daycare)
 {
     u16 species[2];
     u32 otIds[2];
@@ -1248,7 +1343,8 @@ static u8 daycare_relationship_score(struct DayCareData *dayCareData)
     u16 *egg1;
     u16 *egg2;
     struct BoxPokemon *parent;
-    for (i=0, parent=&dayCareData->mons[0], spc=species, ids=otIds, gnd=genders, egg1=&eggGroups[0][0], egg2=&eggGroups[0][1]; i<2; spc++, egg1+=2, egg2+=2, parent++, i++)
+
+    for (i=0, parent=&daycare->mons[0], spc=species, ids=otIds, gnd=genders, egg1=&eggGroups[0][0], egg2=&eggGroups[0][1]; i<2; spc++, egg1+=2, egg2+=2, parent++, i++)
     {
         *spc = GetBoxMonData(parent, MON_DATA_SPECIES);
         *ids++ = GetBoxMonData(parent, MON_DATA_OT_ID);
@@ -1280,7 +1376,7 @@ static u8 daycare_relationship_score(struct DayCareData *dayCareData)
     {
         return 0;
     }
-    if (!sub_80423A8(eggGroups[0], eggGroups[1]))
+    if (!EggGroupsOverlap(eggGroups[0], eggGroups[1]))
     {
         return 0;
     }
@@ -1303,7 +1399,7 @@ static u8 daycare_relationship_score(struct DayCareData *dayCareData)
 }
 #else
 __attribute__((naked))
-static u8 daycare_relationship_score(struct DayCareData *dayCareData)
+static u8 GetDaycareCompatibilityScore(struct DayCare *daycare)
 {
     asm_unified("\tpush {r4-r7,lr}\n"
                     "\tmov r7, r10\n"
@@ -1415,7 +1511,7 @@ static u8 daycare_relationship_score(struct DayCareData *dayCareData)
                     "\tbeq _08042484\n"
                     "\tadd r1, sp, 0x4\n"
                     "\tmov r0, sp\n"
-                    "\tbl sub_80423A8\n"
+                    "\tbl EggGroupsOverlap\n"
                     "\tlsls r0, 24\n"
                     "\tcmp r0, 0\n"
                     "\tbeq _08042484\n"
@@ -1454,17 +1550,17 @@ static u8 daycare_relationship_score(struct DayCareData *dayCareData)
 }
 #endif
 
-u8 daycare_relationship_score_from_savegame(void)
+u8 GetDaycareCompatibilityScoreFromSave(void)
 {
-    return daycare_relationship_score(&gSaveBlock1.daycareData);
+    return GetDaycareCompatibilityScore(&gSaveBlock1.daycare);
 }
 
-void sp0B9_daycare_relationship_comment(void)
+void SetDaycareCompatibilityString(void)
 {
     u8 whichString;
     u8 relationshipScore;
 
-    relationshipScore = daycare_relationship_score_from_savegame();
+    relationshipScore = GetDaycareCompatibilityScoreFromSave();
     whichString = 0;
     if (relationshipScore == 0)
         whichString = 3;
@@ -1474,7 +1570,8 @@ void sp0B9_daycare_relationship_comment(void)
         whichString = 1;
     if (relationshipScore == 70)
         whichString = 0;
-    StringCopy(gStringVar4, gUnknown_08209AC4[whichString]);
+
+    StringCopy(gStringVar4, sCompatibilityMessages[whichString]);
 }
 
 #ifdef NONMATCHING
@@ -1486,12 +1583,12 @@ bool8 NameHasGenderSymbol(const u8 *name, u8 genderRatio)
     // This portion is nonmatching
     flags[1] = 0;
     flags[0] = 0;
-    for (i = 0; name[i] != EOS; i ++)
+    for (i = 0; name[i] != EOS; i++)
     // End nonmatching portion
 
     {
-        if (name[i] == CHAR_MALE) flags[0] ++;
-        if (name[i] == CHAR_FEMALE) flags[1] ++;
+        if (name[i] == CHAR_MALE) flags[0]++;
+        if (name[i] == CHAR_FEMALE) flags[1]++;
     }
     if (genderRatio == MON_MALE && flags[0] && !flags[1]) return TRUE;
     if (genderRatio == MON_FEMALE && flags[1] && !flags[0]) return TRUE;
@@ -1581,45 +1678,48 @@ static u8 *AppendGenderSymbol(u8 *name, u8 gender)
         if (!NameHasGenderSymbol(name, MON_MALE))
             return StringAppend(name, gOtherText_MaleSymbol3);
     }
-
     else if (gender == MON_FEMALE)
     {
         if (!NameHasGenderSymbol(name, MON_FEMALE))
             return StringAppend(name, gOtherText_FemaleSymbol3);
     }
+
     return StringAppend(name, gOtherText_GenderlessSymbol);
 }
 
-static u8 *MonAppendGenderSymbol(u8 *name, struct BoxPokemon *boxMon)
+static u8 *AppendMonGenderSymbol(u8 *name, struct BoxPokemon *boxMon)
 {
     return AppendGenderSymbol(name, GetBoxMonGender(boxMon));
 }
 
-static void DaycareLevelMenuGetText(struct DayCareData *dayCareData, u8 *dest)
+static void GetDaycareLevelMenuText(struct DayCare *daycare, u8 *dest)
 {
-    u8 buffers[2][20];
+    u8 monNames[2][20];
     u8 i;
+
     *dest = EOS;
-    for (i = 0; i < 2; i ++)
+    for (i = 0; i < 2; i++)
     {
-        GetBoxMonNick(&dayCareData->mons[i], buffers[i]);
-        MonAppendGenderSymbol(buffers[i], &dayCareData->mons[i]);
+        GetBoxMonNick(&daycare->mons[i], monNames[i]);
+        AppendMonGenderSymbol(monNames[i], &daycare->mons[i]);
     }
-    StringCopy(dest, buffers[0]);
+
+    StringCopy(dest, monNames[0]);
     StringAppend(dest, gOtherText_NewLine2);
-    StringAppend(dest, buffers[1]);
+    StringAppend(dest, monNames[1]);
     StringAppend(dest, gOtherText_NewLine2);
     StringAppend(dest, gOtherText_CancelAndLv);
 }
 
-static void DaycareLevelMenuGetLevelText(struct DayCareData *dayCareData, u8 *dest)
+static void GetDaycareLevelMenuLevelText(struct DayCare *daycare, u8 *dest)
 {
     u8 i;
     u8 level;
+
     *dest = EOS;
-    for (i = 0; i < 2; i ++)
+    for (i = 0; i < 2; i++)
     {
-        level = Daycare_GetLevelAfterSteps(&dayCareData->mons[i], dayCareData->misc.countersEtc.steps[i]);
+        level = GetLevelAfterDaycareSteps(&daycare->mons[i], daycare->misc.countersEtc.steps[i]);
         dest[0] = 0x34;
         dest[1] = 0xFC;
         dest[2] = 0x14;
@@ -1630,10 +1730,11 @@ static void DaycareLevelMenuGetLevelText(struct DayCareData *dayCareData, u8 *de
         dest[2] = 0x00;
         dest = StringCopy(dest + 3, gOtherText_NewLine2);
     }
+
     *dest = EOS;
 }
 
-static void DaycareLevelMenuProcessKeyInput(u8 taskId)
+static void HandleDaycareLevelMenuInput(u8 taskId)
 {
     if (gMain.newKeys & DPAD_UP)
     {
@@ -1648,7 +1749,7 @@ static void DaycareLevelMenuProcessKeyInput(u8 taskId)
     {
         if (gTasks[taskId].data[0] != 2)
         {
-            gTasks[taskId].data[0] ++;
+            gTasks[taskId].data[0]++;
             MoveMenuCursor(+1);
             PlaySE(SE_SELECT);
         }
@@ -1676,12 +1777,12 @@ void ShowDaycareLevelMenu(void)
 {
     u8 buffer[100];
     MenuDrawTextWindow(15, 6, 29, 13);
-    DaycareLevelMenuGetText(&gSaveBlock1.daycareData, buffer);
+    GetDaycareLevelMenuText(&gSaveBlock1.daycare, buffer);
     MenuPrint(buffer, 16, 7);
-    DaycareLevelMenuGetLevelText(&gSaveBlock1.daycareData, buffer);
+    GetDaycareLevelMenuLevelText(&gSaveBlock1.daycare, buffer);
     MenuPrint_PixelCoords(buffer, 0xce, 0x38, TRUE);
     InitMenu(0, 16, 7, 3, 0, 13);
-    CreateTask(DaycareLevelMenuProcessKeyInput, 3);
+    CreateTask(HandleDaycareLevelMenuInput, 3);
 }
 
 void ChooseSendDaycareMon(void)
diff --git a/src/field/field_control_avatar.c b/src/field/field_control_avatar.c
index e9dd0e9a6..c7b4861d5 100644
--- a/src/field/field_control_avatar.c
+++ b/src/field/field_control_avatar.c
@@ -500,9 +500,9 @@ bool8 sub_8068894(void)
         ScriptContext1_SetupScript(gUnknown_081A14B8);
         return TRUE;
     }
-    if (sub_80422A0())
+    if (ShouldEggHatch())
     {
-        IncrementGameStat(13);
+        IncrementGameStat(GAME_STAT_HATCHED_EGGS);
         ScriptContext1_SetupScript(S_EggHatch);
         return TRUE;
     }
diff --git a/src/pokemon/pokemon_summary_screen.c b/src/pokemon/pokemon_summary_screen.c
index d1d226b80..70b9b7d94 100644
--- a/src/pokemon/pokemon_summary_screen.c
+++ b/src/pokemon/pokemon_summary_screen.c
@@ -52,6 +52,7 @@ void PokemonSummaryScreen_PrintEggTrainerMemo(struct Pokemon *mon, u8 left, u8 t
 
     if (locationMet == 255)
     {
+        // Eggs received from Pokemon Box.
         MenuPrint(gOtherText_EggNicePlace, left, top);
         return;
     }
diff --git a/src/scene/egg_hatch.c b/src/scene/egg_hatch.c
index d363e4bcd..6ea26e546 100644
--- a/src/scene/egg_hatch.c
+++ b/src/scene/egg_hatch.c
@@ -1,26 +1,27 @@
 #include "global.h"
-#include "pokemon.h"
-#include "items.h"
-#include "decompress.h"
 #include "data2.h"
-#include "task.h"
-#include "script.h"
-#include "palette.h"
-#include "overworld.h"
-#include "main.h"
+#include "daycare.h"
+#include "decompress.h"
 #include "event_data.h"
-#include "sound.h"
+#include "ewram.h"
+#include "items.h"
+#include "main.h"
+#include "menu.h"
+#include "naming_screen.h"
+#include "overworld.h"
+#include "palette.h"
+#include "pokemon.h"
+#include "rng.h"
+#include "script.h"
 #include "songs.h"
-#include "text.h"
-#include "text_window.h"
+#include "sound.h"
 #include "string_util.h"
 #include "strings2.h"
-#include "menu.h"
-#include "naming_screen.h"
+#include "task.h"
+#include "text.h"
+#include "text_window.h"
 #include "trig.h"
-#include "rng.h"
 #include "trade.h"
-#include "ewram.h"
 
 extern struct SpriteTemplate gUnknown_02024E8C;
 
@@ -47,7 +48,6 @@ extern const struct SpriteSheet sUnknown_0820A3B8;
 extern const struct SpritePalette sUnknown_0820A3C0;
 
 bool8 GetSetPokedexFlag(u16 nationalNum, u8 caseID);
-u8* GetMonNick(struct Pokemon* mon, u8* dst);
 u8 sav1_map_get_name(void);
 const struct CompressedSpritePalette* GetMonSpritePalStruct(struct Pokemon* mon); //gets pokemon palette address
 void sub_8080990(void);
@@ -391,7 +391,7 @@ _08042B42:\n\
 
 bool8 sub_8042B4C(void)
 {
-    return sub_8042ABC(&gSaveBlock1.daycareData, gSpecialVar_0x8004);
+    return sub_8042ABC(&gSaveBlock1.daycare, gSpecialVar_0x8004);
 }
 
 static u8 EggHatchCreateMonSprite(u8 a0, u8 switchID, u8 pokeID)
diff --git a/src/script_pokemon_util_80C4BF0.c b/src/script_pokemon_util_80C4BF0.c
index 011978a0c..1462a985d 100644
--- a/src/script_pokemon_util_80C4BF0.c
+++ b/src/script_pokemon_util_80C4BF0.c
@@ -573,7 +573,7 @@ u8 ScriptGiveEgg(u16 species)
     struct Pokemon mon;
     u8 isEgg;
 
-    sub_8042044(&mon, species, 1);
+    CreateEgg(&mon, species, TRUE);
     isEgg = TRUE;
     SetMonData(&mon, MON_DATA_IS_EGG, &isEgg);