Celadon Corner Glitch Metamap Script ACE could be used as a "Yellow gm- ACE"
Posted by: Krys3000
Date: 2018-09-03 16:06:28
Hello everyone,
Glitch Meta-map Script ACE is a rather poorly documentated ACE method in Pokémon Red, Blue and Yellow, which relies on using either the Trainer Escape Glitch or the Item Underflow Glitch in the PC (or any other ACE method) to change the value of the address controlling the script for a given map.
Indeed, some (all?) of these addresses can be changed directly by changing the nature or the quantity of the right item beyond the 50th slot using PC underflow.
But, as you probably all know, when performing the Trainer Escape Glitch, we change the escaped trainer's map script to 01 and change it back to 00 when coming back after facing a Pokémon and flashing the start menu (whose textbox ID on every map is 00). And, if reading another textbox than the start menu before getting back on the escaped trainer's map, we can attribute to the script address another value than 00 - the one matching the given textbox ID.
While working a bit on Glitch Metamap Script ACE I noticed that Glitch Script 0x12 of Celadon Corner in Yellow executes codes in both english and french games at $FA4C, an Echo RAM copy of $DA4C. This is the fifth character of the last Daycare Pokémon name in english games (and the safari balls count in french games, which could be noped as well as the following address controlling the presence of a Pokémon in the Daycare to reach the first character in that name).
Of course, I couldn't help but thinking about luckytyphlosion's extensive work on gm- glitch item ACE that I believe could be adapted to this. Executing code would not use gm- but just entering into the Corner!
As a proof of concept I have performed a setup that could be used aswell (of course, it should also work with gm- in R/B provinding that we adapt the jump) derived from the setup I invented for glitch item ACE using 4F. Note that similarly to 4F ACE, if your Daycare as never been used, you can use a 10/11-Stored Pokémon ws m setup and it will work with this method.
- If playing french games, make sure that during your last visit to the Safari Zone, you have come out of time or of Balls.
- Place at the Daycare an un-nicknamed Abra at lvl 80 with currently 24 HP. The O.T. of this Pokémon must be compatible with ACE (e.g.: AAAAAAA)
- If playing french games, take back that Pokémon. You can also do it if playing english games.
- Have in PC Slot 1 a Pokémon with 33 PP currently on first move, 33 PP currently on second move (38 if playing french games), 19 PP currently on third move (3 PP Up used) and no fourth move or no PP on it.
- Have in PC Slot 2 Clefairy, Male Nidoran or Spearow (or another Abra) with currently 233 HP.
This jumps to $D321 (english) or $D326 (french) which is item 3 of the pack. Enter in the Corner to execute the code.
This stays theorical. It seems impossible to Trainer Escape the Rocket in Celadon Corner (except with a glitch item maybe, Evie may know more about this), and I don't know if $D65E, which is the address for the Corner's script, is accessible through the underflow in the PC. If not, then this ACE method would be exclusively limited to the ability to use another ACE Method to setup the script!
If anyone of you has some time to work on this, don't hesitate to do it :)