Ashiok, the Dream Shaper

+1: Search target player's library for up to two creature cards and exile them face down. Then each player shuffles his or her library.
0: Seach target player's library for a creature card and exile it face down. Then each player shuffles his or her library. Transform Ashiok.
: Whenever a creature attacks Ashiok, you may create a 1/1 blue and black Nightmare creature token with flying and wither.