Things You'll Need
Instructions
Obtain a Pikachu in the GBA game. If you're playing a third-generation game, you can catch a Pikachu in the Safari Zone. Pokemon FireRed and LeafGreen players can catch one at the Viridian Forest or at the Power Plant.
Defeat Master Greevil in Pokemon XD Gale of Darkness. Obtain the Hoenn Pokedex if you're trading Pokemon from Sapphire or Ruby. You must beat the Elite Four and obtain the National Pokedex if you want to trade from FireRed, LeafGreen or Emerald.
Start Pokemon XD and head to any Pokemon Center. Walk up one set of stairs and talk to the woman in front of the desk. Save your game and insert the GBA cartridge into the Game Boy Advance. Use a GBA Link Cable to connect the Game Boy Advance to your GameCube.
Turn on the Game Boy Advance. Twelve Pokemon will appear on the screen. The first six will be your party in Pokemon XD, while the last six will be the Pokemon from the GBA game.
Choose the two Pokemon you would like to trade. Once the trade is complete, the memory card of Pokemon XD will update. You will have the option to trade another Pokemon.