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Generation II Glitch Discussion

Is it possible to activate the GS ball event through Japanese PCC glitch? - Page 1

Is it possible to activate the GS ball event through Japanese PCC glitch?

Posted by: Rabby250
Date: 2016-05-31 06:06:18
Hello guys, I've just run into this YouTube video demonstrating the unexpected script execution in PCC when playing on a fresh Japanese Crystal:
[youtube]http://www.youtube.com/watch?v=nqEaRpDEeTw[/youtube]

This reminds me of a rumor back in early 2001, shortly after the release of Japanese Crystal but before the official introduction of GS Ball (the actual distribution took place in May, as I remembered): the rumor, which was never verified, stated that some lucky players received GS Ball from Nurse Joy on their first visit to PCC.

So now I'm wondering: is it possible to trigger the event of Nurse Joy handing out the GS Ball with some specific value on $A800, thereby forming a possible explanation to the rumor? Thanks!

Re: Is it possible to activate the GS ball event through Japanese PCC glitch?

Posted by: Torchickens
Date: 2016-05-31 08:17:59
Interesting that you should post this. Earlier today and yesterday I was looking into how to get a Celebi via the 04 'received Pokémon from a trade' script (thread).


Hello guys, I've just run into this YouTube video demonstrating the unexpected script execution in PCC when playing on a fresh Japanese Crystal:
[youtube]http://www.youtube.com/watch?v=nqEaRpDEeTw[/youtube]

This reminds me of a rumor back in early 2001, shortly after the release of Japanese Crystal but before the official introduction of GS Ball (the actual distribution took place in May, as I remembered): the rumor, which was never verified, stated that some lucky players received GS Ball from Nurse Joy on their first visit to PCC.

So now I'm wondering: is it possible to trigger the event of Nurse Joy handing out the GS Ball with some specific value on $A800, thereby forming a possible explanation to the rumor? Thanks!

That's an interesting rumour and it may be true. It's possible that they started a new game, reached the PCC and the save data happened to have the right value for some reason. If you clear your save file with Up+Select+B in Generation I, it replaces the entire save file with FF. The same might be true with the Japanese version of Pokémon Crystal.

If you start a new game on the emulator BGB without a save file, do not save, and don't use Up+Select+B, save data appears to be 'randomized'; so obtaining the GS Ball this way might be possible. I don't know if this may apply for a real console though, for fresh cartridges.

To force the GS Ball event without cheating, it should be possible with TM14 outside of the TM/HM pocket arbitrary code execution if you open SRAM and write to the relevant address, however, I don't know if you can activate the GS Ball event by changing $A800, and a different address may be responsible.

In English Crystal, you can apparently activate the event by setting 0xBE3C in the save file to 0x0B. So it should be possible by English means as well (if we know the SRAM bank for the 0xBE3C offset address), via a method like TM33 arbitrary code execution.

Re: Is it possible to activate the GS ball event through Japanese PCC glitch?

Posted by: SatoMew
Date: 2016-05-31 18:34:01
The PCC's Trade Corner attendant delivers you the GS Ball in Japanese Crystal when address 0xA000 is set to 0x0B even if the Pokémon Mobile System GB is disabled (its state is controlled by addresses 0xE800 and 0x9000 of the save file).


This reminds me of a rumor back in early 2001, shortly after the release of Japanese Crystal but before the official introduction of GS Ball (the actual distribution took place in May, as I remembered): the rumor, which was never verified, stated that some lucky players received GS Ball from Nurse Joy on their first visit to PCC.


This rumor may be true because I recall being given the GS Ball after a visit to the PCC when I played the game about half a decade ago. Unfortunately, I do not have the files from that period. It's something that I most likely dismissed as an emulation quirk back then.