All permanents on the battlefield. The Ur-Dragon is your commander, does not have summoning sickness, and cannot be blocked by an opponent.
Scion on the battlefield. At least 13 life. available.
All permanents on the battlefield. The Ur-Dragon is your commander. Colossus Hammer attached to The Ur-Dragon.
All permanents on the battlefield. The Ur-Dragon is your commander. Eldrazi Conscription attached to The Ur-Dragon.