The Celestial Toymaker

Whenever The Celestial Toymaker attacks, look at
the top three cards of your library. Exile any
number of them in a face-down pile and the rest in
a face-up pile. Defending player chooses one of
those piles. Put that pile into your hand.

At the beginning of each end step, each opponent loses 2 life for each spell or ability that caused one
or more players to guess or to group cards or permanents into a pile this turn.