Things You'll Need
Instructions
Visit Route 218 and capture a Wild Ditto. Add your adult Arceus to your adventuring party. Return to the Pokemon day care center in Solaceon Town. Save your game and power off your DS.
Connect the DSI Action Replay Max to your computer's USB port and download the latest codes from CodeJunkies. Select Pokemon Diamond and download it onto your device.
Create a new custom code, naming it "InstantBreedingCode." Copy and paste this code into your file:
Select "Pokemon Diamond" from the "My CodeList" section. Right mouse click and select "add new cheat code." Choose "InstantBreedingCode" and save the changes to the Pokemon Diamond cheat.
Insert the Action Replay Max into your DSi. Power it on. The onscreen prompt will ask you to insert your game cartridge. Insert your Pokemon Diamond. The code list loads. Select the "instant breeding" from the available Pokemon codes. Tap the "go" button to launch Pokemon Diamond.
Press and hold the "L and R" buttons. Talk with the daycare man. He will take your Arceus and Ditto and give you an egg. Walk around until your egg hatches and your baby Arceus is born.
"921ED3D0 00000E00
94000130 FEFF0000
121ED3D2 00004280
121ED3EE 000042A5
D2000000 00000000"
Save your cheat code.