How do you catch arceous in Pokemon diamond?

Answer:
You have to either have the event or the action replay code. If you don't want to wait for the event, here's the action replay code:

94000130 FCFF0000
B21C4D28 00000000
B0000004 00000000
0000AA3C EDB88320
2000AA68 0000000A
D2000000 00000000

You will receive the azure flute. Go to spear pillar and it will ask you if you want to play the flute. Say yes. Then you play the flute and the screen goes black. Then when it returns to normal, you will see a golden staricase. Go up it. Then you will step onto a glass platform. Next the battle with arceus begins. You catch it at level 80.

First answer by ID1290818581. Last edit by Ejaffe. Contributor trust: 29 [recommend contributor recommended]. Question popularity: 1 [recommend question].