Necromaster Dragon
Creature — Dragon
Flying
Whenever this creature deals combat damage to a player, you may pay 
. If you do, create a 2/2 black Zombie creature token and each opponent mills two cards.
Mark Zug
Dragons of Tarkir (DTK)
• #226Rulings
Necromaster Dragon’s last ability will trigger once for each player it deals combat damage to. For each of these abilities, you may pay {2} only once.
(wotc • 2015-02-25)
Rulings
Necromaster Dragon’s last ability will trigger once for each player it deals combat damage to. For each of these abilities, you may pay {2} only once.
(wotc • 2015-02-25)