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Hello, I don't know if this is documented anywhere, but recently I have been trying to find out how Platinum generates PIDs for NPC trainers during the main game. I've mainly been examining Pokemon caught with a catch trainer code, some light hex editing on trpoke/data, and looking at the disassembly. So far, I've made the following observations: The lowest byte is either 0x78 or 0x88 depending on the trainer's gender - 0x78 for female, 0x88 for male. This causes Pokemon to be gendered the same as their owner unless they have any sort of existing gender ratio, in which case it's their preference. It also causes all NPC Pokemon to have their first ability. The highest byte is always 0. The middle two bytes are where it's more complex. It seems the sum of species, difficulty, level, and trainer location (not sure if the trainer number or memory address) is used: On the same trainer, a 250 difficulty Armaldo (species 348) has the same PID as a 200 difficulty Staraptor (species 398). On the same trainer, a Level 31 Combee (species 415) has the same PID as a Level 48 Staraptor (species 398). A Fisherman (trainer 175 in the disassembly) with a Level 42 Gyarados has the same PID as another Fisherman's (trainer 174) Level 43 Gyarados. When any of these factors is changed by 1, the value of the middle bytes is incremented (or possibly decremented by its ffff-complement) by a near-constant amount (like, plus or minus 1). If it reaches 0 or ffff, it loops around. This leads me to believe that the previous sum is multiplied by some value, but I cannot parse what. I have noticed that this increment seems to be determined by solely the trainer class as far as the trainer information is concerned. A Fisherman turned into a Rival class (no other modifications) is incremented by the same amount with each Level/Species/Difficulty/Trainer change as an actual fight against the Rival is. Looking into the disassembly seems to verify a lot of these observations: ldrb r0, [r0, #0x0] @ MainGameData_NPCTrainer_Class + r5*0x34 MainGameData_NPCTrainer_Size bl Function_20793ac cmp r0, #0x1 bne branch_207940a mov r0, #0x78 str r0, [sp, #0x14] b branch_207940e branch_207940a: @ 207940a :thumb mov r0, #0x88 str r0, [sp, #0x14] This preceding code assigns either 0x78 or 0x88 and stores that on the stack, which is definitely the eventual gender byte. branch_2079440: @ 2079440 :thumb ldrh r0, [r7, #TrPkmn0_Species] mov r1, #0x3f lsl r1, r1, #10 and r1, r0 asr r2, r1, #10 @ I think the point of all this shifting and anding is to clear the higher bits (that have no legal reason to exist) on the species? It shouldn't affect the value for any legal Pokemon. add r1, sp, #0x64 strb r2, [r1, #0x3] ldr r1, =0x3ff ldrh r2, [r7, #TrPkmn0_0] @ This data is definitely the difficulty. and r0, r1 lsl r0, r0, #16 ldrh r1, [r7, #TrPkmn0_Lvl] lsr r0, r0, #16 str r0, [sp, #0x34] @ Storing the should-be unaffected species on the stack ldr r0, [sp, #0x38] @ NPCTrainerDataAdress add r2, r2, r1 @ Difficulty+Level ldr r1, [sp, #0x34] @ Retrieving the species ldr r0, [r0, #0x18] @ Getting some offset of the "NPCTrainerDataAddress", I presume the location based on my observations add r1, r1, r2 @ (Difficulty+Level)+Species add r0, r0, r1 @ (Difficulty+Level+Species)+Trainer something str r0, [sp, #0x58] @ Sum stored on the stack bl SetPRNGSeed add r0, r4, r5 add r0, #0x29 ldrb r0, [r0, #0x0] @ MainGameData_NPCTrainer_Class + r5*0x34 (this comment is from the disassembly) mov r6, #0x0 cmp r0, #0x0 ble branch_207948c branch_207947a: @ 207947a :thumb bl PRNG str r0, [sp, #0x58] add r0, r4, r5 add r0, #0x29 ldrb r0, [r0, #0x0] @ MainGameData_NPCTrainer_Class + r5*0x34 .hword 0x1c76 @ add r6, r6, #0x1 cmp r6, r0 blt branch_207947a branch_207948c: @ 207948c :thumb ldr r0, [sp, #0x58] @ Retrieving the earlier sum after...something is done to it lsl r1, r0, #8 @ Left shifting to clear the lowest byte ldr r0, [sp, #0x14] @ Retrieving the gender value add r6, r1, r0 @ Adding that gender value to the middle bytes I am pretty sure this is where the process ends, but as you can tell by the lack of comments, the middle branch confuses me. Based on my limited understanding of assembly, I think loops like this are used to simulate multiplication as I theorized earlier, but there's an actual multiplication instruction so I assume it is more complex than that. The big issue is that even looking at the whole file, I am having trouble keeping track of what r4 and r5 should contain at this point, or if there any significance to 0x29 (an offset? idk) or if it's just being used as a constant. I'm also not sure if there's any significance to PRNG being called every time in the loop since iirc this is how player PIDs are generated, but the trainer PIDs don't seem to be random. Writing this out, I realize it's a lot, but I think I'm close and I'm hoping someone more familiar with assembly and Pokemon internally can crack this final bit. Or this has already been discovered and I've wasted a lot of time. For verification purposes, some observed PIDs: 200 Difficulty Level 48 Staraptor on League Barry (Empoleon team, #481): 0x00877488. Level 46: 0x000ae788. Level 47: 0x00c92e88. Level 49: 0x0045ba88 200 Difficulty Level 48 Staraptor on Elite Four Aaron (#261): 0x00e0fb88, Level 49: 0x00b6ec88 200 Difficulty Level 48 Staraptor on Elite Four Bertha (#262): 0x007b1578. Level 47: 0x00a11e78 0 Difficulty Level 43 Gyarados on Fisherman (#175): 0x0079fc88. Level 42: 0x001f2488 0 Difficulty Level 43 Gyarados on Fisherman (#174): 0x001f2488. Level 42: 0x00c44c88

Don't think there's any restriction relating to using Bank. There's restriction related to trading early, but it shouldn't apply to Bank.

So far, ban risk is for having CFW, not for playing with modified saves. It's just that modified saves are a way to show them that you have a CFW'd Switch. Unless done incorrectly, block injections don't traces of modifications. (Unless they happen to be doing a before and after comparison to your save, and your injections is something ridiculous. But that would require them to store both copies of the save on the server at the first place. Who knows really)