Raiden

Ninjutsu {2}{u}{b} ({2}{u}{b} ,Return an unblocked
attacker you control to hand: Put this card
onto the battlefeild from your hand tapped and
attacking.)

Whenever Raiden deals combat
damage to a player, that player exiles the top
two cards of their library. Until end of turn
you may play those two cards without paying there
mana costs.