What are the best moves for Arceus

The best moves for Arceus are:

Judgement
Roar of Time
Spacial Rend
Shadow Force

and I would recommend giving it a Draco Plate.. but any other would work as well :)
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This move list is found on the Event TRU Arceus, and it hardly the best moveset. It is easily walled by a steel-type. Roar of Time is a terrible move in competitive play as it allows a easy revenge kill, or a free turn to set up. Draco Meteor is only slightly weaker, and with much less drawbacks. Also, giving arceus a Draco Plate would make the moves Judgement and Spacial Rend kind of redundant due to both having the same attack power of 100. Its best to choose one (Judgement for accuracy/ Spacial Rend for increased Critical hit ratio) so you can free up a spot for a coverage or support move.