Cheapest priced copy (Dragons of Tarkir): $0.49 at Card Kingdom, near mint, their price list as of .
Necromaster Dragon 
Creature — Dragon · 4/4 · Rare · Dragons of Tarkir · #226
Flying
Whenever this creature deals combat damage to a player, you may pay {2}. If you do, create a 2/2 black Zombie creature token and each opponent mills two cards.
Legal inCommanderPioneerModernLegacyVintage
Not legal inBrawlStandardPauper
3 printings · $0.49 to $0.79 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Dragons of Tarkir | 226 | Rare | $0.49 | $0.49 |
| Dragons of Tarkir Promos | 226 | Rare | — | $0.79 |
| Dragons of Tarkir Promos | 226s | Rare | — | $0.69 |
One ruling from Wizards of the Coast
- 25 February 2015Necromaster 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.