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Author Topic: New Pokemon Yellow Softlock?  (Read 397 times)

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New Pokemon Yellow Softlock?
« on: April 29, 2018, 10:14:17 am »

Detailed in the video, I softlocked after trying to Masterball a MissingNo. in an attempt to duplicate a second item. The Masterball would not stop wiggling, and seemingly, there isn't an end to this. If there is, it's probably followed by a crash, but idk. If anyone has any reasoning as to why this occurs, that would be cool, because I sure don't.

EDIT: I also searched around a bit, and I could not find it documented anywhere else.
« Last Edit: April 29, 2018, 06:28:00 pm by Nackles42 »


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Re: New Pokemon Yellow Softlock?
« Reply #1 on: April 29, 2018, 01:49:16 pm »
This happened to me on cartridge last year on yellow aswell. not sure what causes it, but it def happened to me before. :O

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Re: New Pokemon Yellow Softlock?
« Reply #2 on: April 29, 2018, 03:31:02 pm »
I think I remember when you do the stable unstable MissingNo. trick (MissingNo. is first encounter with save file removed with Up+Select+B; does not work on some emulators but works on BGB) you can catch unstable MissingNo. with no ball rolls or something. I suspect then maybe something is corrupted from its sprite that affects the ball rolls and it's not always the same.

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Re: New Pokemon Yellow Softlock?
« Reply #3 on: April 29, 2018, 05:16:22 pm »
Hmm.... I was using VBA, and it definitely was not the first time I had encountered MissingNo. or other glitch Pokemon (I caught a 4 4Hy and evolved it into Q, for instance). I had definitely saved and reset prior to this. I tried waiting it out, nothing seemed to happen after 255 shakes, so.... I really got nothing on this one. Maybe something would happen after I waited for another number of shakes (65535, for instance) but I have not tried yet, and I doubt it would provide anything other than a crash. Oh well.


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Re: New Pokemon Yellow Softlock?
« Reply #4 on: April 29, 2018, 09:13:56 pm »
Here's what should happen:
  • The game sets the successful animation counters (4-1 = 3 sub-animations, 3 shakes)
  • If it's a Ghost battle, the game overrides it with a null animation (0 sub-anims, 0 shakes)
  • If the battle is the Old Man or Oak type, and event 02F is set (which is *not* the case during the normal Rattata catching demo), then the animation is overridden with the failure animation (play all 5 sub-anims, shake 3 times). Otherwise, the Pokémon is automatically considered captured, which, as explained below, skips any ball-shaking calculations and preserves the value set at step 1
  • Otherwise, if the player is fighting the Ghost Marowak, the animation is set to fail.
  • If the capture succeeds, the game does not perform extra calculations, and skips the following step, thereby preserving the capture value.
  • Finally, the game performs complexicated calculations, which determine the number of ball shakes. This basically amounts to either playing only 1 sub-anim, or playing all 5 sub-anims with different shake amounts
Finally, and using that parameter, the game plays the ball toss animation.

This ends up in the special handler, which first plays the corresponding toss sub-animation, then sub-anims from this sequence.

I haven't looked into the rest much more than finding the ball-shake function.
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