This page is for small hints about how to edit pokecrystal that don't need an entire tutorial of their own. Any sort of tips, tricks, hints, pointers to obscure but useful code routines, engine trivia—it all goes here. ## Contents - [Change the odds of encountering a shiny Pokémon](#change-the-odds-of-encountering-a-shiny-pokémon) - [Stop the blue palette from animating its white hue](#stop-the-blue-palette-from-animating-its-white-hue) - [Make overworld sprites darker at night](#make-overworld-sprites-darker-at-night) - [Enemy trainers have maximum happiness for a powerful Return](#enemy-trainers-have-maximum-happiness-for-a-powerful-return) - [Lowercasing Pokémon names cuts off their first letter](#lowercasing-pokémon-names-cuts-off-their-first-letter) - [Prevent NPCs' heads from flipping when they walk down](#prevent-NPCs-heads-from-flipping-when-they-walk-down) ## Change the odds of encountering a shiny Pokémon The odds of encountering a shiny Pokémon in Gen 2 are 1 in 8,192. That value isn't literally defined anywhere: it's a consequence of making shininess based on DVs. A shiny Pokémon has: - Attack DV = 2, 3, 6, 7, 10, 11, 14, or 15 - Defense, Speed, and Special DVs = 10 Since all four DVs are random from 0 to 15, some multiplication shows that 1 in 8,192 Pokémon will be shiny. The routine that checks those specific values is `CheckShininess` in [engine/gfx/color.asm](../blob/master/engine/gfx/color.asm). If you want different odds, just change which DVs count as shiny. (The `Unused_CheckShininess` routine right below it would just make a Pokémon shiny if all its DVs are 10 or higher, which gives odds of about 1 in 50.) Also, the red Gyarados has hard-coded values for its DVs of 14/10/10/10; they're defined as `ATKDEFDV_SHINY` and `SPDSPCDV_SHINY` in [constants/battle_constants.asm](../blob/master/constants/battle_constants.asm). ## Stop the blue palette from animating its white hue There are eight palettes used for tilesets: `GRAY`, `RED`, `GREEN`, `WATER`, `YELLOW`, `BROWN`, `ROOF`, and `TEXT`. It's called `WATER` instead of `BLUE` because its lightest hue gets animated for some tilesets, cycling between three colors. This makes water (and rocks, whirlpools, and waterfalls) look more dynamic, but it prevents you from making static blue tiles (like Mart roofs). To stop it, edit [engine/tilesets/tileset_anims.asm](../blob/master/engine/tilesets/tileset_anims.asm) and replace all the instances of `dw NULL, AnimateWaterPalette` with `dw NULL, WaitTileAnimation`. ## Make overworld sprites darker at night Edit [gfx/overworld/npc_sprites.pal](../blob/master/gfx/overworld/npc_sprites.pal): ```diff ; nite - RGB 15,14,24, 31,19,10, 31,07,01, 00,00,00 ; red - RGB 15,14,24, 31,19,10, 10,09,31, 00,00,00 ; blue - RGB 15,14,24, 31,19,10, 07,23,03, 00,00,00 ; green - RGB 15,14,24, 31,19,10, 15,10,03, 00,00,00 ; brown - RGB 15,14,24, 31,19,10, 30,10,06, 00,00,00 ; pink + RGB 15,14,24, 16,10,09, 17,03,00, 00,00,00 ; red + RGB 15,14,24, 16,10,09, 05,04,27, 00,00,00 ; blue + RGB 15,14,24, 16,10,09, 03,10,02, 00,00,00 ; green + RGB 15,14,24, 16,10,09, 08,04,02, 00,00,00 ; brown + RGB 15,14,24, 16,10,09, 18,05,04, 00,00,00 ; pink RGB 31,31,31, 31,31,31, 13,13,13, 00,00,00 ; silver RGB 15,14,24, 08,13,19, 00,11,13, 00,00,00 ; tree RGB 15,14,24, 12,09,15, 08,04,05, 00,00,00 ; rock ``` ## Enemy trainers have maximum happiness for a powerful Return Edit [engine/pokemon/move_mon.asm](../blob/master/engine/pokemon/move_mon.asm): ```diff TryAddMonToParty: ... GeneratePartyMonStats: ; wBattleMode specifies whether it's a wild mon or not. ; wMonType specifies whether it's an opposing mon or not. ; wCurPartySpecies/wCurPartyLevel specify the species and level. ; hl points to the wPartyMon struct to fill. ... ; Initialize happiness. + ld a, [wMonType] + and $f ld a, BASE_HAPPINESS + jr z, .got_happiness + ld a, $ff ; max happiness for enemy trainers +.got_happiness ld [de], a inc de ... ``` ## Lowercasing Pokémon names cuts off their first letter If you simply lowercase all the names in [data/pokemon/names.asm](../blob/master/data/pokemon/names.asm) and rebuild the ROM, the first letter of their names may be missing. The cause is changing `"FARFETCH'D"` to `"Farfetch'd"`, because `'d` is actually a single character. The fix is to pad its name to the same length as all the rest with an `@`, so that it becomes `"Farfetch'd@"`. ## Prevent NPCs' heads from flipping when they walk down When NPCs walk up or down, they flip horizontally every other frame to create the alternating left-right step animation. But for NPCs with asymmetrical faces, this can look awkward when they walk down. To disable this flipping for all overworld sprites, edit [data/sprites/facings.asm](../blob/master/data/sprites/facings.asm): ```diff FacingStepDown3: ; walking down 2 db 4 ; # - db 0, 8, X_FLIP, $80 - db 0, 0, X_FLIP, $81 + db 0, 0, 0, $80 + db 0, 8, 0, $81 db 8, 8, RELATIVE_ATTRIBUTES | X_FLIP, $82 db 8, 0, RELATIVE_ATTRIBUTES | X_FLIP, $83 ``` Note that the player sprite in the naming screen and the Town Map are unaffected by this. Also, this prevents the bicycling player sprite from moving side to side.