How do you obtain and succesfully use the Azure Flute in Pokemon Diamond to capture Arceus?

Question by Brent S: How do you obtain and succesfully use the Azure Flute in Pokemon Diamond to capture Arceus?
I have heard alot of rumors about “going to the man in green” and “hold down L and R as you enter the Pokemart” and sometimes having to use “Action Replay” which I have only just begun to grasp the concept of. I do not want to obtain Arceus by cheats, hacks or illegal play because I’ve heard alot of horror stories about this causing problems in the game, like Pokemon stats going crazy. I do not have Action Replay and I don’t plan to get anything for my DS that wasn’t approved by Nintendo. I have heard repeatedly that “Mystery Gift” has to be activated. Mine is activated because I just found out what you need to do; go to Jubulife TV and talk to …etc. etc.
I want to know if the rumours are true; is it possible to obtain the Azure Flute from Mystery Gift if you select “GET VIA WIRELESS” in Mystery Gift menu or will it have to be “VIA Wi-Fi”? Or is the Azure Flute only obtainable by Action Replay? Or by hacking AKA CHEATING?! I don’t need/want Action Replay and don’t want to cheat.

Best answer:

Answer by spartan-117
I think you are forced to buy a nintendo event and when you go to the place where you caught dialga/palkia in the triangle floor slot thing, you use the azure flute and a stair will appear. You will end up battling arceus.

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