Swamp

Black Knight

First strike (This creature deals combat damage before creatures without first strike.)
Protection from white (This creature can't be blocked, targeted, dealt damage, or enchanted by anything white.)

Yawgmoth's Edict

Whenever an opponent casts a white spell, that player loses 1 life and you gain 1 life.

Terror

Destroy target nonartifact, nonblack creature. It can't be regenerated.

Duress

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

Encroach

Target player reveals their hand. You choose a nonbasic land card from it. That player discards that card.

Sarcomancy

When Sarcomancy enters the battlefield, 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.

Dauthi Horror

Shadow (This creature can block or be blocked by only creatures with shadow.)
Dauthi Horror can't be blocked by white creatures.

Hatred

As an additional cost to cast this spell, pay X life.
Target creature gets +X/+0 until end of turn.

Lake of the Dead

If Lake of the Dead would enter the battlefield, sacrifice a Swamp instead. If you do, put Lake of the Dead onto the battlefield. If you don't, put it into its owner's graveyard.
{T}: Add {B}.
{T}, Sacrifice a Swamp: Add {B}{B}{B}{B}.

Perish

Destroy all green creatures. They can't be regenerated.

Dauthi Slayer

Shadow (This creature can block or be blocked by only creatures with shadow.)
Dauthi Slayer attacks each combat if able.

Deathgrip

Gloom

White spells cost {3} more to cast.
Activated abilities of white enchantments cost {3} more to activate.