The Ur-Dragon {4}{W}{U}{B}{R}{G}

Legendary Creature — Dragon Avatar

Eminence — As long as The Ur-Dragon is in the command zone or on the battlefield, other Dragon spells you cast cost {1} less to cast.

Flying

Whenever one or more Dragons you control attack, draw that many cards, then you may put a permanent card from your hand onto the battlefield.

10/10

Illustrated by Justine Jones

Prints	USD	EUR	TIX
Commander Masters #361	$20.08	€22.31	0.45
Commander Masters #594	$31.27		0.46
Commander Masters #689	$23.78	€22.93	0.41
Commander Masters #1065	✶ $55.48
Secret Lair Drop	✶ $39.74		0.33
Commander 2017 Oversized	✶ $10.08
Commander 2017	✶ $20.83
Treasure Chest			0.11
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You draw one card for each Dragon you controlled that attacked, even if some of them left the battlefield before The Ur-Dragon’s triggered ability resolves. (2017-08-25)
You may only put one permanent card from your hand onto the battlefield, no matter how many Dragons you attacked with or how many players they attacked. (2017-08-25)

If a Dragon you control enters the battlefield attacking, it won’t cause The Ur-Dragon’s last ability to trigger. (2017-08-25)
The Ur-Dragon’s triggered ability resolves after all attackers have been chosen. You can’t attack with some Dragons, put a creature card with haste onto the battlefield, and then attack with that creature. Similarly, any “whenever a creature attacks” abilities of the permanent card you put onto the battlefield won’t trigger. (2017-08-25)