Done Shiny Jirachi legality in pastgens

[CrazyJeff]

What type of bug are you reporting? Validator

What is the bug?
Legal Shiny Jirachi in Gen 3 OU is being read as illegal/not usable.

Seems like the only Shiny Jirachi allowed are the WISHMKR ones, but there are MANY more Shiny Jirachi spreads available via PAL version of Pokemon CHANNEL.

Are you able to replicate it? If so, how?
As far as PkHex is concerned, this Shiny Jirachi is 100% legal and comes from the PAL Version of Pokemon CHANNEL.

This is the Jirachi in question (Showdown Set Format)

Jirachi @ Leftovers
Ability: Serene Grace
Shiny: Yes
EVs: 252 HP / 252 Def / 4 SpA
Relaxed Nature
IVs: 30 HP / 16 Atk / 30 SpD / 29 Spe
- Wish
- Psychic
- Fire Punch
- Calm Mind

Relevant ProjectPokemon Thread from the Event Gallery:

https://projectpokemon.org/home/files/file/2819-channel-shiny-jirachi/

.pk3 File attached

 

[DaWoblefet]

These are the current legal Shiny Jirachi spreads from Gen 3 that Showdown recognizes (which like you said, are just WISHMKR currently):

            {generation: 3, level: 5, shiny: true, nature: "Bashful", ivs: {hp: 24, atk: 3, def: 30, spa: 12, spd: 16, spe: 11}, moves: ["wish", "confusion", "rest"], pokeball: "pokeball"},
            {generation: 3, level: 5, shiny: true, nature: "Careful", ivs: {hp: 10, atk: 0, def: 10, spa: 10, spd: 26, spe: 12}, moves: ["wish", "confusion", "rest"], pokeball: "pokeball"},
            {generation: 3, level: 5, shiny: true, nature: "Docile", ivs: {hp: 19, atk: 7, def: 10, spa: 19, spd: 10, spe: 16}, moves: ["wish", "confusion", "rest"], pokeball: "pokeball"},
            {generation: 3, level: 5, shiny: true, nature: "Hasty", ivs: {hp: 3, atk: 12, def: 12, spa: 7, spd: 11, spe: 9}, moves: ["wish", "confusion", "rest"], pokeball: "pokeball"},
            {generation: 3, level: 5, shiny: true, nature: "Jolly", ivs: {hp: 11, atk: 8, def: 6, spa: 14, spd: 5, spe: 20}, moves: ["wish", "confusion", "rest"], pokeball: "pokeball"},
            {generation: 3, level: 5, shiny: true, nature: "Lonely", ivs: {hp: 31, atk: 23, def: 26, spa: 29, spd: 18, spe: 5}, moves: ["wish", "confusion", "rest"], pokeball: "pokeball"},
            {generation: 3, level: 5, shiny: true, nature: "Naughty", ivs: {hp: 21, atk: 31, def: 31, spa: 18, spd: 24, spe: 19}, moves: ["wish", "confusion", "rest"], pokeball: "pokeball"},
            {generation: 3, level: 5, shiny: true, nature: "Serious", ivs: {hp: 29, atk: 10, def: 31, spa: 25, spd: 23, spe: 21}, moves: ["wish", "confusion", "rest"], pokeball: "pokeball"},
            {generation: 3, level: 5, shiny: true, nature: "Timid", ivs: {hp: 15, atk: 28, def: 29, spa: 3, spd: 0, spe: 7}, moves: ["wish", "confusion", "rest"], pokeball: "pokeball"},

To implement, we'd need details on either some mechanism for how Gen 3 Shiny Jirachi IV spread + Natures are calculated, or a list of all possible combinations. We don't have support for valid IV/Nature combinations in Gen 3 in general right now (which is another bug too). Not sure which is more reasonable to implement.

 

[Anubis]

To implement, we'd need details on either some mechanism for how Gen 3 Shiny Jirachi IV spread + Natures are calculated, or a list of all possible combinations. We don't have support for valid IV/Nature combinations in Gen 3 in general right now (which is another bug too). Not sure which is more reasonable to implement.

I used PKHeX core to generate all possible shiny CHANNEL Jirachi spreads and got 116172 results. This matches with a post on Reddit claiming that total.

I put all of the spreads with nature and Hidden Power info into this spreadsheet for easier viewing and sorting: HERE

I believe it was an intentional decision not to enforce general PIDIV correlation for applicable mons in gen 3-4, as it would make it very hard for users to know which spreads they can use. With this many shiny spreads vs the few for WISHMKR only, perhaps the solution isn't to restrict to this huge list.

 

[DaWoblefet]

Discussion in the #sim-dev channel of the Smogon Development Discord has led to approval of allowing any Shiny Jirachi with that Pokemon Channel source.

Right now, we don't restrict for otherwise impossible Nature/IV combinations in Gen 3/4 because 1) we don't have support for computing legal Nature/IV combinations, 2) it would presumably be time-consuming on the server to actually compute legal combinations and 3) we don't have a good method of allowing users to pick legitimate Nature/IV combinations.

Since we don't have a system in place for validating Gen 3-4 IV/Nature combinations in general, Shiny Jirachi can follow this pattern of being allowed on Showdown even with, say, perfect IVs and the user's choice of Nature. To be clear, this is a compromise; ideally, we would have support for PIDIV validation.

EDIT: Fixed by Karthik in https://github.com/smogon/pokemon-showdown/pull/10408