Have

Ghastly Gloomhunter

Kicker {3}{B} (You may pay an additional {3}{B} as you cast this spell.)
Flying, lifelink
If this creature was kicked, it enters with two +1/+1 counters on it.

Festering Goblin

When this creature dies, target creature gets -1/-1 until end of turn.

Shepherd of Rot

{T}: Each player loses 1 life for each Zombie on the battlefield.

Shambling Goblin

When this creature dies, target creature an opponent controls gets -1/-1 until end of turn.

Vault of Whispers

Black Cat

When this creature dies, target opponent discards a card at random.

Dark Ritual

Shambling Ghast

When this creature dies, choose one —
• Target creature an opponent controls gets -1/-1 until end of turn.
• Create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Pestilence

At the beginning of the end step, if no creatures are on the battlefield, sacrifice this enchantment.
{B}: This enchantment deals 1 damage to each creature and each player.

Duress

Target opponent reveals their hand. You choose a noncreature, nonland card from it. That player discards that card.

Swamp

Moan of the Unhallowed

Create two 2/2 black Zombie creature tokens.
Flashback {5}{B}{B} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Gurmag Angler

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)

Tortured Existence

{B}, Discard a creature card: Return target creature card from your graveyard to your hand.

Gravepurge

Put any number of target creature cards from your graveyard on top of your library.
Draw a card.

Rite of Consumption

As an additional cost to cast this spell, sacrifice a creature.
Rite of Consumption deals damage equal to the sacrificed creature's power to target player or planeswalker. You gain life equal to the damage dealt this way.

Don't Have

Grave Scrabbler

Madness {1}{B} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)
When this creature enters, if its madness cost was paid, you may return target creature card from a graveyard to its owner's hand.

Butcher Ghoul

Undying (When this creature dies, if it had no +1/+1 counters on it, return it to the battlefield under its owner's control with a +1/+1 counter on it.)

Corrupted Conviction

As an additional cost to cast this spell, sacrifice a creature.
Draw two cards.

Deadly Dispute

As an additional cost to cast this spell, sacrifice an artifact or creature.
Draw two cards and create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Carrion Feeder

This creature can't block.
Sacrifice a creature: Put a +1/+1 counter on this creature.

Nested Shambler

When this creature dies, create X tapped 1/1 green Squirrel creature tokens, where X is this creature's power.

Village Rites

Cast Down

Mortician Beetle

Whenever a player sacrifices a creature, you may put a +1/+1 counter on this creature.

Echoing Return

Return target creature card and all other cards with the same name as that card from your graveyard to your hand.

Grixis Slavedriver

When this creature leaves the battlefield, create a 2/2 black Zombie creature token.
Unearth {3}{B} ({3}{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.)

Rotten Reunion

Exile up to one target card from a graveyard. Create a 2/2 black Zombie creature token with decayed. (It can't block. When it attacks, sacrifice it at end of combat.)
Flashback {1}{B} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Gempalm Polluter

Cycling {B}{B} ({B}{B}, Discard this card: Draw a card.)
When you cycle this card, you may have target player lose life equal to the number of Zombies on the battlefield.