The Gatekeeper
Identity — Traitor (U)
Unveil {4} (Start the game with this identity face down in the command zone. Turn it face up any time for its unveil cost.)
When The Gatekeeper is unveiled, create Cerberus, a legendary 4/8 black and red Hound creature token with menace, double strike, trample, and lifelink.
{2}: Turn The Gatekeeper face down.