From Glitch City Laboratories
The Fire Spin glitch is a miscellaneous glitch which is only known to exist within the first generation of the Pokémon games. By definition, it is a glitch which activates an oversight in the two-player capabilities of the game's battling system. On one user's side, one of his or her Pokémon has not fainted, but on the other user's side the same Pokémon has fainted, meaning that transmission errors will persist until the battle ends.
- Two players.
- Access to the Cable Club.
- A working link cable.
- Player One requires a Pokémon knowing Mirror Move.
- Player Two requires a Pokémon knowing Fire Spin.
- On Player One's side; a Pokémon which could be defeated in one move by Fire Spin.
- Ideally Player One should have the Pokémon knowing Mirror Move as the first party member.
- Ideally Player Two should have the Pokémon knowing Fire Spin as the first party member.
- Both players should enter the Cable Club and request a battle.
- In battle, Player One should send out the Pokémon knowing Mirror Move and Player Two should send out the Pokémon knowing Fire Spin.
- Player Two should perform the move Fire Spin first, whilst Player One should use Mirror Move.
- Due to Mirror Move's priority; the turn should end before the move is used.
- Player Two should switch his/her Pokémon to one that can be defeated in one hit by Fire Spin.
- If performed correctly, on Player Two's screen Mirror Move will fail and his/her Pokémon would not faint. On Player One's screen however, the game considers that Player Two's Pokémon has fainted.
- The game will then translate data from other parts of the RAM to manage what will happen next in battle, for example; what Pokémon Player One switches to. The TMTRAINER effect is common here.
-  - The Fire Spin glitch, originally posted on GCL forums by SloshedMail.