This message is for all those that have an Action Replay.
If you want Darkrai without going to an event, this is what you must do.
1) Activate the Walk Anywhere code on the AR.
2) Go to Canalave City and take the ship to Full Moon Island.
3) When you arrive on the island, start walking East (right).
4) When you have walked far enough New Moon Island will appear.
5) Go to the center of the island, and battle Darkrai.