Xerranth Tevek, Unx Tyrant

For each player, search that player's library for a
card and exile it, then that player shuffles their
library. You choose a nonland card exiled this
way. Until end of turn, you may cast that card,
and you may spend mana as though it were mana
of any type to cast it.
{3}{u}{b}{r}: Destroy target creature. You may draw
cards equal to its power. If you do, you lose life
equal to its toughness.