An addendum to the Fossil conversion glitch
Posted by: Torchickens
Date: 2013-03-14 11:10:13
This is because byte D68A (fly byte 1), and D68B (fly byte 2) are changed to the switched Pokémon's fourth move and Trainer ID byte 1 (a multiple of 256) respectively.
If 'fly byte 1' is invalid, the game will most likely freeze when you open the Fly menu.
[img]http://i.minus.com/j1g5ictdi8lYT.png[/img]
Therefore, you have to make sure that 'fly byte 1' is valid. I recommend 7F (Waterfall) (Goldeen learns it at level 37 and Seaking learns it at level 39) - which will give you at worst (with the Player ID byte 1 as 00) Saffron City, Fuschia City and the Pokémon League omitted, and at best only Fuschia City omitted.
Having move 4 as FF is unfortunately impossible, unless there's a certain glitch Pokémon that learns it but trying to switch it to position 4 could probably mess up the game.
Here are a list of valid Fly location IDs. I missed out the ones that skip certain towns and invalid ones that bring up a freeze like the screenshot above:
Pallet Town only: 01, 00
Pallet Town, Virdian City: 03, 00
Pallet Town, Virdian City, Pewter City: 07, 00
Pallet Town, Virdian City, Pewter City, Cerulean City: 0F, 00
Pallet Town, Virdian City, Pewter City, Cerulean City, Lavender Town: 1F, 00
Pallet Town, Viridian City, Pewter City, Cerulean City, Lavender Town, Vermilion City: 3F, 00
Pallet Town, Viridian City, Pewter City, Cerulean City, Lavender Town, Vermilion City, Celadon City: 7F, 00
Pallet Town, Viridian City, Pewter City, Cerulean City, Lavender Town, Vermilion City, Celadon City, Fuschia City: FF, 00
Pallet Town, Viridian City, Pewter City, Cerulean City, Lavender Town, Vermilion City, Celadon City, Fuschia City, Cinnabar Island: FF, 01
Pallet Town, Viridian City, Pewter City, Cerulean City, Lavender Town, Vermilion City, Celadon City, Fuschia City, Cinnabar Island, Pokémon League: FF, 03
Pallet Town, Viridian City, Pewter City, Cerulean City, Lavender Town, Vermilion City, Celadon City, Fuschia City, Cinnabar Island, Pokémon League, Saffron City: FF, 07
Apparently, another bad side effect of the glitch is not being able to Surf, due to getting the 'と できな' message unless you use the ????? (07h) item, obtainable with the make your own items glitch. I haven't been able to replicate this myself, even though the music does initially tend to change to the cycling theme. Does anyone know why the not being able to Surf side effect happens?