Conundrum Sphinx

Conundrum Sphinx

Creature - Sphinx | Power/Toughness: 4 / 4 (CMC 4)
Flying
Whenever Conundrum Sphinx attacks, each player chooses a card name. Then each player reveals the top card of their library. If the card a player revealed has the name they chose, that player puts it into their hand. If it doesn't, that player puts it on the bottom of their library.