Have

Shepherd of Rot

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

Duress

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

Nameless Inversion

Changeling (This card is every creature type.)
Target creature gets +3/-3 and loses all creature types until end of turn.

Swamp

Barren Moor

This land enters tapped.
{T}: Add {B}.
Cycling {B} ({B}, Discard this card: Draw a card.)

Getting

Ghoulraiser

When this creature enters, return a Zombie card at random from your graveyard to your hand.

Geth's Verdict

Target player sacrifices a creature of their choice and loses 1 life.

Sylvok Lifestaff

Equipped creature gets +1/+0.
Whenever equipped creature dies, you gain 3 life.
Equip {1}

Diabolic Edict

Target player sacrifices a creature of their choice.

Siege Zombie

Tap three untapped creatures you control: Each opponent loses 1 life.

Ghoulcaller's Chant

Choose one —
• Return target creature card from your graveyard to your hand.
• Return two target Zombie cards from your graveyard to your hand.

Festering Mummy

When this creature dies, you may put a -1/-1 counter on target creature.

Sultai Emissary

When this creature 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.)

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.)

Carrion Feeder

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

Defile

Target creature gets -1/-1 until end of turn for each Swamp you control.

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.

Lazotep Reaver

When this creature enters, amass Zombies 1. (Put a +1/+1 counter on an Army you control. It's also a Zombie. If you don't control an Army, create a 0/0 black Zombie Army creature token first.)

Village Rites

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

Quicksand

{T}: Add {C}.
{T}, Sacrifice this land: Target attacking creature without flying gets -1/-2 until end of turn.