Loona, Hellhound

Disguise Commander {3}{b}{b} (You can Disguise
from the command zone. Commander tax applies.)

When Loona is turned face up, put a doublestrike counter on it and it fights target creature.

When Loona Enters or is turned face up, search
your library for a card with lower mana value than
the amount of mana spent to cast Loona or use its
disguise ability and reveal it. You lose life equal to its
mana value and add it to your hand.