well, you will have to wait a few weeks, because his mystery gift isn't out yet in the US. But it will be in a few weeks, just keep checking on Pokemon com and Pokemon platinum com, and when the mystery gift is out, it is the azure Flute and you have to go to spear pillar, and there will be a stair case and there is arceus! But be careful, he is lv. 80 so he is difficult to catch, I'd save right before I go into spear pillar, so if you kill him, you could turn off the ds and turn it on and do it again until you capture the ultimate Pokemon!
girantia, darkri and arceus
you get the myster gift in a Nintendo event
yes, with action replay ds select arceus.
The rival's starter gets up to level 85
All Legendary Pokemon you can catch in Platinum: Giratina, Azelf, Mesprit, Uxie, Dialga, Palkia, Heatran, Regigigas, Cresselia, Darkrai, Articuno, Zapdos, Moltress, Regirock, Regice, Registeel, Shaymin, Arceus. (Darkrai, Shaymin, and Arceus can only be got by events).
arceus is an event pokemon.
Pokemon Diamond, Pearl, and Platinum have Arceus.
You can only get Arceus by an Event.
me
You can't catch Arceus. You can only catch Arceus in Pokemon Platinum.
Arceus.
Arceus
you can not get arceus with no action replay
Golden Arceus
Arceus
Arceus
Pokemon platinum you can also get shaymin