When Gray Merchant of Asphodel enters, each opponent loses X life, where X is your devotion to black. You gain life equal to the life lost this way. (Each {B} in the mana costs of permanents you control counts toward your devotion to black.) 2/4
Whenever Headless Rider or another nontoken Zombie you control dies, create a 2/2 black Zombie creature token. 3/1
Destroy target nonblack creature. At the beginning of your next upkeep, pay {2}{B}. If you don’t, you lose the game.
As Engineered Plague enters, choose a creature type. All creatures of the chosen type get -1/-1.
At the beginning of your upkeep, sacrifice a permanent. Whenever Greater Harvester deals combat damage to a player, that player sacrifices two permanents.
When Boggart Harbinger comes into play, you may search your library for a Goblin card, reveal it, then shuffle your library and put that card on top of it.
At the beginning of your upkeep, the Ring tempts you. Whenever you choose a creature as your Ring-bearer, you may pay 2 life. If you do, draw a card.
Roll two d10 and choose one result. Return a creature card from your graveyard to the battlefield with a number of +1/+1 counters on it equal to that result. Then each opponent loses X life and you gain X life, where X is the other result.
Champion a Goblin (When this comes into play, sacrifice it unless you remove another Goblin you control from the game. When this leaves play, that card returns to play.) Whenever a Goblin you control deals combat damage to a player, you may put a 1/1 black Goblin Rogue creature token into play.
T: Add 1 to your mana pool. 2WB, T: Creatures you control gain deathtouch and lifelink until end of turn.
Menace, lifelink Whenever a Knight you control deals combat damage to a player, put a +1/+1 counter on that creature and create a Blood token. (It's an artifact with "1, T, Discard a card, Sacrifice this artifact: Draw a card.")
Flying Whenever Butcher of Malakir or another creature you control dies, each opponent sacrifices a creature.
Whenever another Zombie you control enters, put a +1/+1 counter on Champion of the Perished.
At the beginning of each opponent's upkeep, you manifest the top card of that player's library. (Put it onto the battlefield face down as a 2/2 creature. Turn it face up for its mana cost if it's a creature card.) Whenever a creature you control but don't own dies, its owner loses 2 life and you gain 2 life.