Things You'll Need
Instructions
Insert your "Pokemon Pearl" game into your Action Replay DS cartridge; check for looseness and turn on your Nintendo DS. Click the "star" icon to reach a game list. Choose "Pokemon Pearl" and proceed to the next screen.
Check the game name and game ID before entering in your code. Type in the Action Replay DS code "94000130 fcff0000 B21c4d28 00000000 B0000004 00000000 10001170 00000182 D2000000 00000000." This code generates a Deoxys in the place of a fossil Pokemon normally obtained at the Oreburgh Museum. Name your code and save; tap "Start" to boot your game.
Fly to Oreburgh City. Before entering, clear a space in your Pokemon party for your Pokemon. Hold the "L" and "R" buttons to activate the code while walking into the Oreburgh Museum on the northeast side of the city. Talk to the scientist at the desk ahead to receive a Level 20 Deoxys.