Glitch City Laboratories Archives

Glitch City Laboratories closed on 1 September 2020 (announcement). This is an archived copy of a thread from Glitch City Laboratories Forums.

You can join Glitch City Research Institute to ask questions or discuss current developments.

You may also download the archive of this forum in .tar.gz, .sql.gz, or .sqlite.gz formats.

Generation I Glitch Discussion

Pokémon Yellow Save Destruction (3DS VC) - Page 1

Pokémon Yellow Save Destruction (3DS VC)

Posted by: SuperGlitchy
Date: 2019-07-03 08:43:42
Hi. Long time listener, first time caller… in half of a decade.

I've been doing a living dex while capturing all Pokémon in their home generation, and it was going fairly well. I was lurking around on IGN/GameFAQs and someone had suggested a very interesting way of doing the long range trainer glitch. Without using Ditto or a specific special stat. It seemed fairly intriguing to me, and I was looking for a stable MissingNo. (apparently x4 harder to encounter on Yellow VC than cartridge) to get lots of rare candies.

Note: I used the debug menu on VC to make the game go x10 its normal speed. I doubt this had anything to do with the save file, however.

I'm sure it's nothing new, but here are the steps I took:

1. Fly away from the kid west of the Cerulean bridge.
2. Save my game by changing a PC BOX and restarting the game.
3. Fly away from the gambler near Lavender Town.
4. Save my game by changing a PC box and restarting a game.
5. Battle a trainer that is more than one tile away.
6. Talking to a NPC that wants to trade and selecting 'NO'
* Here's the thing with this one: The tutorial said to use the girl who asks for a Cubone south of Cerulean, but I had already traded her so I had the genius idea of going to the Pokémon lab in Cinnabar instead. More on this later.
7. Fly to Cerulean.
8. Go up to Nugget Bridge. The menu pops up, but instead of pressing B, I flew to Lavender Town as per the tutorial.
9. Fight a Level 80 Starmie as SOON as I landed outside the Pokémon center.
* This actually changed based on the trainer I spoke to. I eventually did try the girl in Cerulean. Here's my results.
Cubone for Machoke Girl: Level 80 Starmie
Golduck for Rhydon: Level 80 Starmie
Growlithe for Dewgong: Level 100+ Electrode
Kangaskahn for Muk: Level 100+ Kingler
10. Walk to Route 8.
11. Press B when the start menu comes up, triggering another battle.

There's quite a lot of RNG involved in this and that was kind of fun about it. It seemed as if each NPC had their own batch of Pokémon that was encounter-able after speaking to them because I would encounter the same few or so. Sometimes glitch trainers appeared or trainers who had the wrong roster. Several times I encountered Lance with an unglitched 152 level Squirtle or Bruno with Blaine's team.

All of the MissingNo. encounters I had seen so far had crashed my game, but I was able to trigger a battle with and actually 'fight' it because the cry was sped through. Until the game crashed, haha.

On one of my encounters after 100+ Kingler, I encountered a glitch Pokémon that crashed the game on encounter. Not the first time. Shrugged it off, reset through the debug menu, was ready to play some more RNGesus. File was gone. No indication of corruption.

Okay, cool! It seems valid on SaveDataFiler. Oh, it won't open on PKHex? Or Rhydon? This isn't good. I opened up the file in a hex editor and compared it to a 'clean' file and it seems the entirety of Bank 1 was overwritten with garbage.

[img]https://i.ibb.co/nwyBjNS/hello2.png[/img]
[img]https://i.ibb.co/3hRDnCX/hello3.png[/img]

First one is garbage, second one is clean. Let me reiterate, this Pokémon did not use any move whatsoever or barely even showed its sprite. The game crashed two seconds after encountering it.

I get my mistake. :P I really should have made a back up of my file using JKSV before I did this, but it didn't cross my mind that merely encountering a glitch Pokémon would erase my file. I mean, I have several cartridges and have abused them a lot glitch-wise, but outside of Super glitch or other ZZAZZy shenanigans, the Bank 1 being overwritten on encounter has NEVER happened to me. While it sucks to have to restart my dex, I think it might be a lot less hair raising to do it in Red and Blue anyways… I'm more surprised that I encountered anything like this and dealing with RNG was kind of fun. (Not sarcastic)

If this has happened to you, please tell me! I might try to recreate it on a copy VC (force a different title ID) but not risking my main file ever again with something like that.

Re: Pokémon Yellow Save Destruction (3DS VC)

Posted by: Couldntthinkofaname
Date: 2019-07-03 09:38:47
Ah, good ol RST 38!


In a lot of crashes in R/B, the crash happens because codeflow is redirected to address 0038. This address contains a single instruction, rst 38. This instruction loops back and back to 0038, causing the crash.

However, because rst is a call instruction, "0039", the next address, get constantly pushed to the stack, causing an overflow. In most cases, the save file is locked, so the  stack overflow is inconsequential to your save. However, for some reason (maybe related to VC inaccuracy of save data), your save was unlocked, causing "0039" to trash your save file.

Better luck next time.

Re: Pokémon Yellow Save Destruction (3DS VC)

Posted by: Torchickens
Date: 2019-07-03 09:39:07
Hi SuperGlitchy!

Yes, if you talk to a trade NPC before activating the encounter; you can get different Pokémon. This was noted by Paco81 but was analysed later. The Pokémon is determined by the fifth/sixth character of the trade Pokémon's nickname.

Red/Blue yields

Route 2 - Abra for Mr. Mime (MARCEL): Level 139 Snorlax
Route 5 - Nidoran for Nidoran (SPOT): Level 80 Missingno. (50h, Dec: 80)
Route 11 - Nidorino for Nidorina (TERRY): Level 80 Starmie
Route 18 - Slowbro for Lickitung (MARC): Level 80 Missingno. (50h, Dec: 80)
Cerulean City - Poliwhirl for Jynx (LOLA): Level 80 Missingno. (50h, Dec: 80)
Vermilion City - Spearow for Farfetch'd (DUX): Level 80 Missingno. (50h, Dec: 80)
Cinnabar Island - Raichu for Electrode (DORIS): Level 80 Missingno. (92h, Dec: 146)
Cinnabar Island - Venonat for Tangela (CRINKLES): Level 139 Kingler
Cinnabar Island - Ponyta for Seel (SAILOR): Level 145 Clefable

Yellow yields

Route 2 - Clefairy for Mr. Mime (MILES): Level 80 Missingno. (92h, Dec: 146)
Route 5 - Cubone for Machoke (RICKY): Level 80 Starmie
Route 11 - Lickitung for Dugtrio (GURIO): Level 80 Clefable
Route 18 - Tangela for Parasect (SPIKE): Level 80 Snorlax
Cinnabar Lab - Golduck for Rhydon (BUFFY): Level 80 Starmie
Cinnabar Lab - Growlithe for Dewgong (CEZANNE): Level 141 Electrode
Cinnabar Lab - Kangaskhan for Muk (STICKY): Level 152 Kingler

Yes, if you do this for a double Trainer escape glitch; you can get a wide range of Pokémon because the above have random DVs, and given their level the number of Pokémon you can get will vary a lot.

This can be abused for a way of finding stable MissingNo. (I think a speedrunner may have found it) The chance of getting a Fossil/Ghost MissingNo. this way is something like 1/8 (??) sorry, can't remember and you can keep soft resetting to try again.

https://www.youtube.com/watch?v=73fAlzIbi9k

As for the save corruption, I'm sorry to hear about your save. :( 3DS Virtual Console through experience seems more likely to erase your save file if you view freezing sprites, press A on long name items at the wrong place, walk out of bounds, etc.

Hope this helps.

Re: Pokémon Yellow Save Destruction (3DS VC)

Posted by: SuperGlitchy
Date: 2019-07-03 09:52:37
Thank you so much for the in-depth explanation, both of you! Accumulating 60 Pokémon or so didn't take too long on x10 speed, and I'm not too mad because this is pretty interesting.

It's crazy that VC allows that. It also kind of sucks that even Nintendo's own emulation is inaccurate to that of a cartridge. Time to be a bit more careful with backing up data– what I should have been doing all along.

Have a great day.  :)

Re: Pokémon Yellow Save Destruction (3DS VC)

Posted by: Torchickens
Date: 2019-07-03 09:55:37

Thank you so much for the in-depth explanation, both of you! Accumulating 60 Pokémon or so didn't take too long on x10 speed, and I'm not too mad because this is pretty interesting.

It's crazy that VC allows that. It also kind of sucks that even Nintendo's own emulation is inaccurate to that of a cartridge. Time to be a bit more careful with backing up data– what I should have been doing all along.

Have a great day.  :)


You're welcome. ^^ Hope you have a great day too!