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?
Well, Pikasprey found a way to escape from my Lorelei lock by having Rage miss 20 times in a row, so I decided to find a way to escape his Ditto Struggle-blocking lock by using Mirror Move 256 times in a row.
Oooooh, so that's why the glitch kept happening to him around Fuchsia City. Because this is where high-enough leveled Spearow/Fearow appear. Cool :D I love weird edge-case glitches like this that get discovered by accident.
Man, Gen 1 is an interesting beast. Good games, but very glitchy. And not necessarily bad glitchy, but *fascinatingly* glitchy. And to think even now we're still finding new flaws in the programming. It's actually pretty impressive.
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.
The fact that this glitch stayed unknown and undocumented really says a lot to how much glitches were in these games. I suppose it's because this one isn't really the most flashy of glitches... and by "flashy", I mean "it doesn't slaughter the graphics and produce a cacophony of cursed noises".
Excellent work answering this question. It's great that you have so much knowledge to share about how these games are programmed. I think you should consider teaming up with someone who does voice overs or do them yourself. The text on screen format is hard to follow when you're dealing with such a complex subject. I also think your writing could be made more concise. I find myself pausing your videos constantly just to make sure I have enough time to read and understand the block of text.
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.)
It's wild how a simple challenge like the "Ditto only" challenge can reveal flaws in the games' coding that would never be found during normal gameplay. I can't imagine something like that would have ever been play tested before the games' release.
If you swapped Mirror Move to the first slot and used it, would it increase the PP of Transform if you swapped it back? If you didn't swap it back, would it increase the PP of Cooltrainer?
Two questions came to mind: 1. What happens if you try to trade a virtual console RBY Ditto that struggles to Struggle, to a gen VII game? Does the Poké Bank check for this anomaly and reject it, or does it fix the spaghetti code, accept Ditto and let it use Struggle? 2. Say you exploit this or any other glitch to get an 8F ("legitimate") Mew with an absurd amount of PP on one or more of its moves, does the Poké Bank let that through?
Oh shit, we can't modify a Pokemon's moves' attributes directly in place, or the effects will be permanent instead of going away after the battle. Okay, just make a copy of the attributes for that data. Oh shit, for PP it change *should* be permanent, so we should be modifying it on the original. Okay, make an exception and modify both just for that case. Oh shit, when you're Transformed, we *shouldn't* modify the original because the PP is temporary. Okay, make an exception and only modify it once just for that case. Oh shit, when you use Mirror Move we're decrementing the PP twice because we play the using-a-move animation twice and for some reason our gameplay logic is coupled tightly with our animation code. Okay, make an exception and re-increment it if you're using Mirror Move. The moral of the story: don't program like this, kids.
What happens if you trade it to Gen 2. Gen 2 does some things a little bit differently so it possible that it could clean up the corruption, even if just incidentally.
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.
Fascinating! I was hoping for an explanation after Pikasprey's video. :) I'm wondering though, when does the code in the games change this mechanic? Does it get fixed in Gold/Silver/Crystal?
Plus by exploiting this you can give PP's to the Cooltrainer move without using a PP-healing item Just Mirror Move once and then swap Mirror Move with the first move
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.
So could the Ditto Struggle-block be avoided if you put Transform into whatever moveslot Mirror Move shows up in? That way, using Mirror Move while transformed is increasing the PP of Transform, rather than increasing the PP of a null/empty move?
The Drowzee used DIsable and it failed, before the softlock happened. What's up with that? Very cool video, I can now sleep at night again, thank you lol
Would it be possible to just change mirror move to slot 1 after transforming, therefore making transform the only move affected, not the non-existent ones? I don't remember if you cannot change move slots after transforming or not but sounds like a solution planning ahead.
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.
1. I'm under the impression that the video leaves out a detail that could make escaping the "lock" way harder: it doesn't just have to be Mirror Move users you battle, MM must be in the same slot as when you first used it, or you'll get multiple empty slots with positive PP; am I right? 2. What happens if, when doing this with a Mew, the slot that should get its PP increased has max PP? Do the PP still increase or not? 3. Would it be possible to hack the Ditto to have 4 Transform slots, 3 of which have 0 max PP? Would that prevent the increase of PP? Would that anyway just solve the lock problem or also cause other problems (e.g. Pokemoncenter healing checks moveslots to restore PP and doesn't like identical moves or max-0-PP moves)?
Hey Crystal can you make a video regarding the pokemon trainer battles on pokemon gen 2 games. About how do they they level up and how that game mechanics really work? because if i remember correctly the befriended trainers who offer some and item and do some battles do level up. i am just wondering how that mechanic really work. thanks.
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??
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.
A bit confused about the Disable softlock. If the game runs a loop to find a non-zero move with PP >0 , shouldn't it just lookup the entire ram for that. After all, thats Gen I programming :D Or is it the only place they put an out-of-bounds check?
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.
An easy enough fix would be to move Transform into whatever slot the pokemon you're coyping has metronome\mirror move in before using it. As long as every battle only has one pokemon with that move, it's all gud.
FanDUMB: "Pokémon Scarlet and Violet are the worst games ever because they're a glitchy, buggy mess!!!" Generation 1: "(sticks head through a random hole in the wall) Are you sure about that?"
So, that explains what happened to Pikasprey Yellow, since he did make use of Mirror Move known by the opposition. Also, I think I recall having a Pokémon with 34/32 PP on one of its moves long ago, and I couldn't figure out how that happened. I do remember I loved fooling around with Metronome a lot back then, so perhaps I got Transform against an opponent that knew Mirror Move, and used that a couple times. Hmm... Correct me if I'm wrong, but because of how PP and PP Ups work in Gen. 1, wouldn't it take only 63 additional uses of Mirror Move or Metronome to get the current PP of the unused moveslot back down to 0 after the initial use that triggers the glitch? Because if you were to hit 64 PP, it would actually flip a bit in the PP byte that's related to the number of PP Ups used, and then the game will read the current PP as 0... if I'm remembering how all this works correctly, that is. (If I am right, then any multiple of 64 added to that 63 would also work, which does include the number 255.)
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.
Ditto is a silly Pokemon.
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.
Well, Pikasprey found a way to escape from my Lorelei lock by having Rage miss 20 times in a row, so I decided to find a way to escape his Ditto Struggle-blocking lock by using Mirror Move 256 times in a row.
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... ua-cam.com/video/TeWxEbl2kWQ/v-deo.html
i was wondering if this was something to do with pikasprey XD
Thanks Crystal_ for the info!
It is always 256.
Oooooh, so that's why the glitch kept happening to him around Fuchsia City. Because this is where high-enough leveled Spearow/Fearow appear. Cool :D I love weird edge-case glitches like this that get discovered by accident.
Man, Gen 1 is an interesting beast. Good games, but very glitchy. And not necessarily bad glitchy, but *fascinatingly* glitchy. And to think even now we're still finding new flaws in the programming. It's actually pretty impressive.
Just the person I was looking for after Pikasprey's Ditto video. Thanks for the explanation!
This sort of pettiness is why I love the glitching community
Was excited to see this after seeing the pikasprey vid. It's pretty amazing how we're still finding obscure bugs in r/b/y.
Perfect complement to the pikasprey video. Love your videos!
The stuff you put out is criminally underrated. Always enjoy seeing your videos
This is awesome. I didn’t expect anyone to solve Pikasprey’s Ditto dilemma.
Haha the first thing I thought after the Pikasprey video was I wonder if anyone has analyzed this glitch yet. And...voila!
What a quick response damn Crystal_ youre impressive!
Well that was quick. Man I love your videos crystal.
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.
I still keep learning things about Pokemon Gen I even 20 years later...
This is the first ever UA-cam video that s full of text but I find satisfying to watch. Good job Crystal
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.
Thanks for making this, I was really curious after seeing Pikasprey's video. The gen 1 community really knows everything.
Why do I find random glitches like this from an ancient game so fascinating lol?
0:57 Dang it man, you made me look at my own Discord window!
The fact that this glitch stayed unknown and undocumented really says a lot to how much glitches were in these games.
I suppose it's because this one isn't really the most flashy of glitches... and by "flashy", I mean "it doesn't slaughter the graphics and produce a cacophony of cursed noises".
So instead of being a "Struggle has pp" error, it is a coding error that makes pp values go out of parameters.
I was close enough, I guess.
Excellent work answering this question. It's great that you have so much knowledge to share about how these games are programmed. I think you should consider teaming up with someone who does voice overs or do them yourself. The text on screen format is hard to follow when you're dealing with such a complex subject. I also think your writing could be made more concise. I find myself pausing your videos constantly just to make sure I have enough time to read and understand the block of text.
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.)
The Struggle is real to get back Struggle!
Haha I love this! Saw his video yesterday and this is a fantastic explanation to the mystery! Thank you!
Dude, yes. I'm so excited that this came out so quickly!
Not all Heros wear capes
Not all Dittos can Struggle. :P
Not all comments are original.
Uranus Not all comments are right.
22 years after these games were released, and we're STILL finding new ways they can royally fuck up. Absolutely incredible.
[PIKASPREY INTENSIFIES]
Now, that's a catchy tune!
It's wild how a simple challenge like the "Ditto only" challenge can reveal flaws in the games' coding that would never be found during normal gameplay. I can't imagine something like that would have ever been play tested before the games' release.
If you swapped Mirror Move to the first slot and used it, would it increase the PP of Transform if you swapped it back? If you didn't swap it back, would it increase the PP of Cooltrainer?
Exactly.
I've seen people say that doing this might cause other glitches to happen, so be careful if your going to attempt that.
**sigh**
I wonder why they didn't make a check so that if the selected move was Mirror Move or Metronome, no PP would be deducted from the base move.
This is really fascinating. Cool video.
Two questions came to mind:
1. What happens if you try to trade a virtual console RBY Ditto that struggles to Struggle, to a gen VII game? Does the Poké Bank check for this anomaly and reject it, or does it fix the spaghetti code, accept Ditto and let it use Struggle?
2. Say you exploit this or any other glitch to get an 8F ("legitimate") Mew with an absurd amount of PP on one or more of its moves, does the Poké Bank let that through?
I'm pretty sure the Ditto will go through just fine.
Great video as always, Crystal_
Oh wow, this already got figured out? Man, you are fast
Well... You solved the problem that Pikasprey was having. GGs c;
Are there any strange interactions with these moves and Mimic?
0:56~(Or 00:58 to be exact), is that a Discord ping sound I hear in the background, or is my mind playing tricks on me? X3
Oh shit, we can't modify a Pokemon's moves' attributes directly in place, or the effects will be permanent instead of going away after the battle. Okay, just make a copy of the attributes for that data.
Oh shit, for PP it change *should* be permanent, so we should be modifying it on the original. Okay, make an exception and modify both just for that case.
Oh shit, when you're Transformed, we *shouldn't* modify the original because the PP is temporary. Okay, make an exception and only modify it once just for that case.
Oh shit, when you use Mirror Move we're decrementing the PP twice because we play the using-a-move animation twice and for some reason our gameplay logic is coupled tightly with our animation code. Okay, make an exception and re-increment it if you're using Mirror Move.
The moral of the story: don't program like this, kids.
What happens if you trade it to Gen 2. Gen 2 does some things a little bit differently so it possible that it could clean up the corruption, even if just incidentally.
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.
Fascinating! I was hoping for an explanation after Pikasprey's video. :)
I'm wondering though, when does the code in the games change this mechanic? Does it get fixed in Gold/Silver/Crystal?
The GSC battle engine is so different to the RBY one, that rather than strictly fixing it, it just didn't introduce the glitch.
Plus by exploiting this you can give PP's to the Cooltrainer move without using a PP-healing item
Just Mirror Move once and then swap Mirror Move with the first move
So if you reordered the moves so that Mirror Move was in the top slot would Transform then gain the PP and you avoid the bug entirely?
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
So could the Ditto Struggle-block be avoided if you put Transform into whatever moveslot Mirror Move shows up in? That way, using Mirror Move while transformed is increasing the PP of Transform, rather than increasing the PP of a null/empty move?
ferrishthefish If you wanna get the Cooltrainer glitch, then do it.
So if mirror move was used in different slots. you would have two non 0PP moves and no way to check?
oh no your ditto forgot how to use struggle too
I guess this explains the ditto only run
how did Disable succeed? Why doesn't the Pokecenter heal Transform?
Didn't someone so a Ditto challenge run where this happened to them?
Yes. The investigation on that glitch after that playthrough was uploaded actually resulted in this very video.
that is one crazy bug
boy how much i love this fucking music
The Drowzee used DIsable and it failed, before the softlock happened. What's up with that?
Very cool video, I can now sleep at night again, thank you lol
... the video. maybe watch it
Would it be possible to just change mirror move to slot 1 after transforming, therefore making transform the only move affected, not the non-existent ones? I don't remember if you cannot change move slots after transforming or not but sounds like a solution planning ahead.
if you change transform to another slot and don't change it back, this glitch happens: ua-cam.com/video/rsNKOARx_AY/v-deo.html
Could you get around this by changing the location of mirror move to the first slot with select?
But you have to make sure to change it back before the battle ends, or else youd end up with the cooltrainer glitch move
Possible fix?
1. Swap mirror move to slot 1
2. Run away
3. Go to Pokemon Centre
4. Swap Transform back
But, how can we do step 4...
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
I don't understand why disable doesn't softlock on it's first use? Can someone explain that to me?
I watched Pikasprey's video the other day. Gosh dang, these games just keep getting more and more broken.
What happens if you trade a Ditto with PP in an empty move slot to Gen 2? Does it have any interesting effects there?
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?
nice to see why it the glitch happened.
1. I'm under the impression that the video leaves out a detail that could make escaping the "lock" way harder: it doesn't just have to be Mirror Move users you battle, MM must be in the same slot as when you first used it, or you'll get multiple empty slots with positive PP; am I right?
2. What happens if, when doing this with a Mew, the slot that should get its PP increased has max PP? Do the PP still increase or not?
3. Would it be possible to hack the Ditto to have 4 Transform slots, 3 of which have 0 max PP? Would that prevent the increase of PP? Would that anyway just solve the lock problem or also cause other problems (e.g. Pokemoncenter healing checks moveslots to restore PP and doesn't like identical moves or max-0-PP moves)?
What if you were to menu swap the moves and have mirror move be at the top? Would that make any difference?
That would be the method to obtain a Ditto with the already documented cooltrainer glitch move.
Hey Crystal can you make a video regarding the pokemon trainer battles on pokemon gen 2 games. About how do they they level up and how that game mechanics really work? because if i remember correctly the befriended trainers who offer some and item and do some battles do level up. i am just wondering how that mechanic really work. thanks.
It's very simple, rematch parties were just made by hand. Like: github.com/pret/pokecrystal/blob/master/data/trainers/parties.asm#L1399-L1427
Hey Crystal_, are you, by any chance, one of the guys that keeps contributing to pret's Pokemon disassemblies on github?
I work on poketcg and ocassionaly the others, what's up?
Wanted to thank you for your contributions. You and Rangi particularly.
I found the explanation about the PP increments hard to understand, is there a visual version anywhere?
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. :)
That is super interesting!
A bit confused about the Disable softlock. If the game runs a loop to find a non-zero move with PP >0 , shouldn't it just lookup the entire ram for that. After all, thats Gen I programming :D
Or is it the only place they put an out-of-bounds check?
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.
An easy enough fix would be to move Transform into whatever slot the pokemon you're coyping has metronome\mirror move in before using it. As long as every battle only has one pokemon with that move, it's all gud.
I was the 256th like on Crystal_'s comment, but I've always been struggling my whole life.
FanDUMB: "Pokémon Scarlet and Violet are the worst games ever because they're a glitchy, buggy mess!!!"
Generation 1: "(sticks head through a random hole in the wall) Are you sure about that?"
Why doesn't using a pokecenter fix it?
only non-empty moveslots have their pp healed
dude honestly youre a fucking genius
So, that explains what happened to Pikasprey Yellow, since he did make use of Mirror Move known by the opposition. Also, I think I recall having a Pokémon with 34/32 PP on one of its moves long ago, and I couldn't figure out how that happened. I do remember I loved fooling around with Metronome a lot back then, so perhaps I got Transform against an opponent that knew Mirror Move, and used that a couple times.
Hmm... Correct me if I'm wrong, but because of how PP and PP Ups work in Gen. 1, wouldn't it take only 63 additional uses of Mirror Move or Metronome to get the current PP of the unused moveslot back down to 0 after the initial use that triggers the glitch? Because if you were to hit 64 PP, it would actually flip a bit in the PP byte that's related to the number of PP Ups used, and then the game will read the current PP as 0... if I'm remembering how all this works correctly, that is. (If I am right, then any multiple of 64 added to that 63 would also work, which does include the number 255.)
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.
0:58 discord
As a programmer myself, after watching videos like these, I can't stop but laughing at the sheer amount of bugs and untested things lol
Why not just narrate this?
Exactly 77 views and 27 likes.
This was also the 7th comment.
Today's date halved would be the 7th.
Ireland has spoken.
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