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- Note: This may corrupt your save
- Enter the GTS (Global Trade Station).
- Deposit the Pokémon that you want to clone.
- Select any level 100 Pokémon in exchange, so no one will take your Pokémon.
- Click "Yes" to confirm trade.
- Once the Pokémon shows up and looks like it's about to be put in a Poké Ball, turn off your DS.
- Turn on your DS and reload the game.
- Check your party. Your Pokémon should still be with you.
- Enter GTS and retrieve your Pokémon that is stored inside.
Transfer more than six Pokémon per day
You will need two Pokémon GBA games to do this trick. This trick works with Pokémon Sapphire, Pokémon Emerald, and Pokémon Diamond - though it should work with any combination of games. You can do this an unlimited amount of times.
- Migrate from the game pak of your choice.
- Change the time on your DS.
- Insert a second Pokémon game pak, and switch your DS back on.
- Load up your Pokémon game as normal.
- Click the Migrate option.
- Follow the normal process to transfer Pokémon, choosing "Yes" both times.
- The game will then give you this message: "You are using a different Nintendo DS, or its internal clock has been altered. If the game's time setting is changed, you will not be able to migrate Pokémon for another 24 hours. Would you like to change your game's time setting to match the Nintendo DS?"
- Choose "Yes" and wait while the DS configures your Pokémon game.
- After the game reloads the title screen, turn the power off.
- Remove your second game pak and insert the first one again.
- Start up the Nintendo DS and start your Pokémon game as normal.
- Once the title screen has loaded, select the Migrate option.
- Now follow the normal process of migrating Pokémon as usual, choosing six Pokémon and confirming migration.
- Afterwards, go to Pal Park and capture all the Pokémon.
- Note: This only works in the Japanese versions.
- Give the item you want to clone to any Pokémon.
- Put that Pokémon first in your party, and a Ditto in second.
- Battle a double-battle.
- Transform Ditto into the Pokémon that has the item.
- Switch the Pokémon holding the item to a Pokémon that knows the move Thief.
- Use Thief against the Ditto and finish the battle.
- Now you have two of that item.