Polluted Delta

{T}, Pay 1 life, Sacrifice Polluted Delta: Search your library for an Island or Swamp card, put it onto the battlefield, then shuffle.

Swamp

Rotlung Reanimator

Whenever Rotlung Reanimator or another Cleric dies, create a 2/2 black Zombie creature token.

Cabal Therapy

Choose a nonland card name. Target player reveals their hand and discards all cards with that name.
Flashback—Sacrifice a creature. (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Vendetta

Destroy target nonblack creature. It can't be regenerated. You lose life equal to that creature's toughness.

Gempalm Polluter

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

Tangle Wire

Fading 4 (This artifact enters with four fade counters on it. At the beginning of your upkeep, remove a fade counter from it. If you can't, sacrifice it.)
At the beginning of each player's upkeep, that player taps an untapped artifact, creature, or land they control for each fade counter on Tangle Wire.

Ancient Tomb

{T}: Add {C}{C}. Ancient Tomb deals 2 damage to you.

Putrid Imp

Discard a card: Putrid Imp gains flying until end of turn.
Threshold — As long as seven or more cards are in your graveyard, Putrid Imp gets +1/+1 and can't block.

Recurring Nightmare

Sacrifice a creature, Return Recurring Nightmare to its owner's hand: Return target creature card from your graveyard to the battlefield. Activate only as a sorcery.

Bloodstained Mire

{T}, Pay 1 life, Sacrifice Bloodstained Mire: Search your library for a Swamp or Mountain card, put it onto the battlefield, then shuffle.

Priest of Gix

When Priest of Gix enters, add {B}{B}{B}.

Duress

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

City of Traitors

When you play another land, sacrifice City of Traitors.
{T}: Add {C}{C}.

Snuff Out

If you control a Swamp, you may pay 4 life rather than pay this spell's mana cost.
Destroy target nonblack creature. It can't be regenerated.

Dark Ritual

Sarcomancy

When Sarcomancy enters, create a 2/2 black Zombie creature token.
At the beginning of your upkeep, if there are no Zombies on the battlefield, Sarcomancy deals 1 damage to you.