you have to get the arceus event on mystery gift.
You can't.
definitely a Nintendo event
You can't
you can't
the only way you can obtain arceus without an action replay is to participate in a Pokemon event. arceus was given out on a movie event. you can also trade with others online on the global terminal or trading friend codes with someone who does have arceus.
You must have gone to an event, where you received the Azure Flute.
You would have to go to a Nintendo event to get a certain item.
Wait for the Nintendo Event. It has not happened as of December 2008.
you need action replay.
no you cannot catch arceus in pokemon black without action replay
the best Pokemon in diamond is arceus, but you have to use action replay or wi-fi mystery gift
nope