Naoko, Pursuing Samurai

Bushido 2 (Whenever this creature blocks or becomes blocked, it gets +2/+2 until end of turn.)
Whenever Naoko, Pursuing Samurai deals combat damage to a player, choose one --
* Exile the top card of that player's library.
* Until end of turn, you may cast a card
exiled with Naoko without paying its mana
cost.