Pokemon R/B/Y - Transform + Mirror Move / Metronome PP glitch 

I figured it had something to do with 256 uses, considering how dependant everything in RBY is on hex values.

Well pikasprey released a video of him struggling with the strugle problem you just explained... ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-TeWxEbl2kWQ.html

i was wondering if this was something to do with pikasprey XD

Thanks Crystal_ for the info!

It is always 256.

Let's see... If you grind Sunkern to L100 and max out its stat experience, its stats will look like this: HP: 233-263 All other stats: 128-158 Think you can beat Red's L70+ team with that?

Sunkern evolves though. Unown on the other hand...

Pikasprey Yellow tis why im getting a ditto plush :3

HowlingSnail I'm recalling Slowflake's rants... Unown is literally Un-own. It's like Abra, but without the TMs/HMs or evolution!

Jayesper Unown is the worst fully evolved Pokémon. The worst overall is Cosmog though.

Not as quick as your message lol

Crystal_ lol

Crystal_ yeah lol. I was the first one besides you.

MeepManToy/Hydrazine and I was the first one to notice 77 views 27 likes... Ireland has spoken. Again.

That's the ultimage goal since I'm unwilling to put the extra required effort to use another format (I'd rather use that effort to put up an extra video instead, and still I barely upload anyway). So thanks.

Not all Dittos can Struggle. :P

Not all comments are original.

Uranus Not all comments are right.

I agree with the voiceover stuff. As for the code, the assembly is available so that you don't even have to disassemble the ROM yourself. Anyone can go study how these bugs work with trivial ease. The only small barrier to entry is that you need an advanced understanding of Z80 assembly. :p (Fortunately, assembly languages are broadly similar enough that knowing x86 or MIPS, which are what I've studied, or any other major ISA is sufficient to make sense of Z80.)

Exactly.

I've seen people say that doing this might cause other glitches to happen, so be careful if your going to attempt that.

The GSC battle engine is so different to the RBY one, that rather than strictly fixing it, it just didn't introduce the glitch.

I'm pretty sure the Ditto will go through just fine.

... the video. maybe watch it

Struggle still works the same in Gen 2 so you still wouldn't be able to use it. Disable works differently in GSC though, since it targets the last used move. I'm not sure if there's any action that could fix it, but healing wouldn't in Gen 2 either.

ferrishthefish If you wanna get the Cooltrainer glitch, then do it.

You'd still need to remember to put the first move back in the first slot before finishing the battle, or else you'll end up with the infamous cooltrainer glitch move instead of Trasnform.

Seems like a small price to pay to avoid having to use mirror move 256 times 🤔

Or simply just do not use Mirror Move xD

I work on poketcg and ocassionaly the others, what's up?

Wanted to thank you for your contributions. You and Rangi particularly.

Of course that's slot 1, where's the damn edit button on mobile...

Swapping a Ditto's moves around after it uses Transform is a great way to royally screw things up. Ever heard of the Cooltrainer Glitch?

E-102 Gamma there are ways to nullify the glitch.

what did slot say first? ​@@renakunisaki

if you change transform to another slot and don't change it back, this glitch happens: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-rsNKOARx_AY.html

The problem with that is that your current PP would reflect 1-3 PP Ups, and the max PP would reflect 0 PP Ups. Struggle does mask the PP Ups so you should be able to fix that, I think Disable still had a weird glitch with PP Ups though. Good point though, 64/128/192 PP should also work to let you use Struggle automatically.

But you have to make sure to change it back before the battle ends, or else youd end up with the cooltrainer glitch move

That would be the method to obtain a Ditto with the already documented cooltrainer glitch move.

Yes. The investigation on that glitch after that playthrough was uploaded actually resulted in this very video.

I'm checking and Struggle works the same so still wouldn't be able to use it. Disable works differently in GSC though, since it targets the last used move.

GSC as in Pokemon Gold, Silver and Crystal?

I'm not a glitch-hunter or a professional at this kind of thing, but I'll try to explain it in less technical terms when using Mirror Move or Metronome, the game believes the active Pokemon uses two moves, so it takes two pp from the moveslot. then, because it was technically only one move, it adds 1 pp to that moveslot. the problem with Ditto is that it normally has no pp in any moveslot except the first (which is Transform), and Mirror Move/Metronome is a little buggy in that it can't take pp from a moveslot that has none but it can add pp to that moveslot, and it makes no exception for a moveslot that normally has no moves or is at full pp (see the example in the video with Mew; the fourth move had more than max pp after the Mirror Move glitch was used) so, as a result, the game believes Ditto has pp in the second/third/fourth moveslot (whichever moveslot was taken by Metronome/Mirror Move while transformed) while it is out of Transform pp in the first slot, which results in the game not allowing Ditto to use Struggle because it still has pp, even though that pp is not attached to any move and can't be used. the game can't read a number higher than 255, so if Mirror Move/Metronome is used 256 times in the same moveslot while transformed, the number will overflow (Stryder7x has a good video explaining overflow/underflow, look for "stryder7x hitting a block") and the game will read a 0 for the pp value of that moveslot and allow Ditto to use Struggle again. does this make sense??

LuckyKoneko Yes, that made sense. Thank you very much for replying and for your time. :D

It's not so much that the game can't _read_ a value higher than 255 as it is that I can't _store_ it. A given move's PP is probably stored in a single byte, which has 256 possible iterations. That's 0-255 inclusive, because in computing, counting starts at 0. When a move's PP is at 255, the corresponding byte would read "11111111." In order to add one to that byte, it would have to gain another digit, which just doesn't happen, so it overflows instead, "incrementing" to 00000000, or 0 in decimal.

thank you for explaining that! I didn't know exactly how it worked.

Any time. :)

It's very simple, rematch parties were just made by hand. Like: github.com/pret/pokecrystal/blob/master/data/trainers/parties.asm#L1399-L1427

That kind of algorithm is for when you want to search for the first occurrence of something. Here you need to draw random numbers between 0 and 3, so you are always within the moves or PP array.

Irish Empire maybe I'm just an uncultured swine but what does 77 and 27 have to do with ireland?

7 is considered the lucky number of Ireland.

MeepManToy/Hydrazine I wouldn't call you an uncultured swine, I would call you an American or whatever people who live in USA are called

Irish Empire well you'd be correct lol

MeepManToy/Hydrazine lol

Wouldn't work, since part of the rage softlock is Dewgong spamming rest in an attempt to deal super effective damage against a psychic type opponent. The AI would be able to use damaging moves against Ditto and will therefore eventually KO it.

only non-empty moveslots have their pp healed

Not really. Integer overflows are a pretty basic concept in programming. If a variable hits the max amount its bits will allow for, it overflows down to the minimum.

Just realized I used too much word salad. That was fucking stupid of me. Let me clarify: Lets say that an 8 bit integer (a number that can't be a decimal) hits 127 and tries to add 1 to that number. Instead of going to 128, it will go down to -128 instead. This is because each bit can hold a 1 or a 0, and an integer using 8 bits can only hold 255 different combinations of 1s and 0s.

shut up