Return to Dust

Oracle Text

Exile target artifact or enchantment. If you cast this spell during your main phase, you may exile up to one other target artifact or enchantment.

Card Rulings

9/25/2006 Regardless of when Return to Dust is cast, its controller may choose one target or two targets. It can always be cast even if there’s only one legal target. If it’s cast at a time other than its controller’s main phase and a second target is chosen, nothing will happen to that target.