Deny Reality

Cascade (When you cast this spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom in a random order.)
Return target permanent to its owner's hand.

Cascade (When you play this spell, remove cards from the top of your library from the game until you remove a nonland card that costs less. You may play it without paying its mana cost. Put the removed cards on the bottom in a random order.)
Return target permanent to its owner's hand.

Warhammer 40,000 Commander

Cascade (When you cast this spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom of your library in a random order.)
Return target permanent to its owner's hand.