Well you can go to the arceus event when the movie Arceus and the sky diamond comes out.
that is a past event try a gllich
You cannot obtain Arceus without hacking or cheating.
NO only with a arceus flute.
you need to get a azureflute
The arceus event is already over, so now you can not get him without cheating.
It is virtually impossible to get Arceus without cheating on Pokemon diamond, pearl, or platinum. You can only encounter Arceus by either cheating or with an event. The same thing goes with the azure flute. ) :
You can't get it without cheating.
Currently No. Arceus was released by event in 2009 and is not intended to be released again.
As of now, there is no way of catching Arceus without cheating or hacking.
Not without cheating
it isn't possible without cheating
Unfortunately, it's impossible without cheating. :(
You can only get Arceus through Nintendo events if you don't want to use cheating devices.