Sphinx of Stolen Secrets

Flying
When Sphinx of Stolen Secrets enters the
battlefield, look at the top four cards of target
opponent's library and separate them into two
piles. That opponent puts one pile into exile face
up, and the other pile into their graveyard.
You may play cards exiled by Sphinx of Stolen
Secrets. You can use mana to cast spells this way
as though it were mana of any type.