Rotting Mastodon

Unholy Hunger

Destroy target creature.
Spell mastery — If there are two or more instant and/or sorcery cards in your graveyard, you gain 2 life.

Untamed Hunger

Enchant creature
Enchanted creature gets +2/+1 and has menace. (It can't be blocked except by two or more creatures.)

Gray Merchant of Asphodel

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.)

Dregscape Zombie

Unearth {B} ({B}: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the next end step or if it would leave the battlefield. Unearth only as a sorcery.)

Returned Reveler

When Returned Reveler dies, each player mills three cards.

Voracious Null

{1}{B}, Sacrifice another creature: Put two +1/+1 counters on Voracious Null. Activate only as a sorcery.

Returned Centaur

When Returned Centaur enters, target player mills four cards.

Gravedigger

When Gravedigger enters, you may return target creature card from your graveyard to your hand.

Warpath Ghoul

Grotesque Mutation

Target creature gets +3/+1 and gains lifelink until end of turn. (Damage dealt by the creature also causes its controller to gain that much life.)

Shambling Attendants

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)
Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)

Grim Guardian

Constellation — Whenever Grim Guardian or another enchantment you control enters, each opponent loses 1 life.

Cruel Revival

Destroy target non-Zombie creature. It can't be regenerated. Return up to one target Zombie card from your graveyard to your hand.

Swamp

Sidisi's Pet

Lifelink (Damage dealt by this creature also causes you to gain that much life.)
Morph {1}{B} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Artificer's Hex

Enchant Equipment
At the beginning of your upkeep, if enchanted Equipment is attached to a creature, destroy that creature.

Hound of the Farbogs

Delirium — Hound of the Farbogs has menace as long as there are four or more card types among cards in your graveyard. (A creature with menace can't be blocked except by two or more creatures.)

Viscera Dragger

Cycling {2} ({2}, Discard this card: Draw a card.)
Unearth {1}{B} ({1}{B}: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the next end step or if it would leave the battlefield. Unearth only as a sorcery.)

Minotaur Abomination

Sultai Emissary

When Sultai Emissary dies, manifest the top card of your library. (Put that card onto the battlefield face down as a 2/2 creature. Turn it face up any time for its mana cost if it's a creature card.)

Viper's Kiss

Enchant creature
Enchanted creature gets -1/-1, and its activated abilities can't be activated.

Gutter Skulk

Crippling Blight

Enchant creature
Enchanted creature gets -1/-1 and can't block.

Corpse Churn

Mill three cards, then you may return a creature card from your graveyard to your hand. (To mill three cards, put the top three cards of your library into your graveyard.)

Rottenheart Ghoul

When Rottenheart Ghoul dies, target player discards a card.

Undead Minotaur

Zombie Goliath

Crow of Dark Tidings

Flying
When this creature enters or dies, mill two cards. (Put the top two cards of your library into your graveyard.)

Unholy Strength

Enchant creature
Enchanted creature gets +2/+1.

Demon's Grasp

Target creature gets -5/-5 until end of turn.

Death's Approach

Enchant creature
Enchanted creature gets -X/-X, where X is the number of creature cards in its controller's graveyard.