duplicating pokemon with XD or colosseum

[Lord Kokkei]

First, you need two memory cards, one containing the file of colosseum or XD with the pokemon you want. Put an empty memory card into slot A and copy the file from slot A to slot B, now you should have a colosseum or XD file in both memory card A and memory card B. Trade the pokemon from card B to a game pak and you can do whatever you want with it.

 

[Forci Stikane]

The only way to "duplicate" them is to catch pointless pokemon in the GBA games (like Poochyena, Zigzagoon, etc., just nothing non-replaceable) en-masse, then trade them for ALL the pokemon in the GCN game, then restart the GCN game.