Agents of Dukauren

Cowl {1}{u}{b} (You may cast this creature face down
as a 2/2 creature for {3}. Whenever it attacks and isn't
blocked, you may turn it face up for its cowl cost.)
Face down Ninjas you control can't be blocked
except by Ninjas.
Whenever a face up Ninja you control deals
combat damage to a player, that player discards
a card and you draw a card.