Catch Opponents Pokemon
Here is a code to allow you to catch another trainer's Pokemon during battle. Make sure you have saved your game before trying out this code in case it goes wrong and you get a bad egg, more on this below the code.
Master code
D8BAE4D9 4864DCE5
A86CDBA5 19BA49B3
Add this code as GameShark before adding the following code.
Catch Other trainer Pokemon
B6C5368A 08BE8FF4
B8D95CFE 06ED6EA1
E151C402 8A229A83
8E883EFF 92E9660D
Activate both codes, and then while you are in battle, hold down l+r together before throwing your Pokeball and you should then catch your opponent's Pokemon.
Bad Egg Warning
Some players may get a bad egg instead of the Pokemon, if this happens to do you don't save the game as you won't be able to get rid of the bad egg.
Getting a bad egg could depend on a number of things including the version of the game you are playing, and which emulator you are using.
Alternative Code
You can also try entering this code as a Codebreaker code without the Master Code. There is also some more information about using this Catch Trainers Pokemon as an Action Replay Code here - Catch Trainers Pokemon
More tricks, tips and cheats for this game are right here - Pokemon Emerald cheats
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