Flying Whenever Thief of Sanity deals combat damage to a player, look at the top three cards of that player's library, exile one of them face down, then put the rest into their graveyard. You may cast that card for as long as it remains exiled, and mana of any type can be spent to cast it.
NM-Mint - $1.00
Lightly Played - $0.90
Moderately Played - $0.80
Heavily Played - $0.70
Damaged - $0.50
NM-Mint Non English - $1.00
Lightly Played Non English - $0.90
Moderately Played Non English - $0.80
Heavily Played Non English - $0.70
Damaged Non English - $0.50