Displacement Wave

Oracle Text

Return all nonland permanents with converted mana cost X or less to their owners' hands.

Card Rulings

6/22/2015 If a permanent has an in its mana cost, that X is 0.
6/22/2015 A token has converted mana cost 0 unless it’s a copy of something else, in which case it has the mana cost of whatever it’s copying.