Vextos, Harbinger of Agony

When Vextos, Awakened Apocalypse enters the battlefield or attacks reveal a number of cards off
the top of target player's library equal to the
number of creatures you control. You may put a creature from among them on the battlefield, then destroy target non land permanent with converted
mana cost less then or equal to the converted
mana cost of the chosen creature. You may put
the rest of the cards either on the bottom of that
player's library or in their graveyard.