Crypt Rats

{X}: Crypt Rats deals X damage to each creature and each player. Spend only black mana on X.

Barren Moor

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

Thorn of the Black Rose

Deathtouch
When Thorn of the Black Rose enters, you become the monarch.

Cast Down

Seekers' Squire

When Seekers' Squire enters, it explores. (Reveal the top card of your library. Put that card into your hand if it's a land. Otherwise, put a +1/+1 counter on this creature, then put the card back or put it into your graveyard.)

Swamp

Tendrils of Corruption

Tendrils of Corruption deals X damage to target creature and you gain X life, where X is the number of Swamps you control.

Wrench Mind

Target player discards two cards unless they discard an artifact card.

Corrupt

Corrupt deals damage to any target equal to the number of Swamps you control. You gain life equal to the damage dealt this way.

Liliana's Specter

Flying
When Liliana's Specter enters, each opponent discards a card.

Defile

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

Chittering Rats

When Chittering Rats enters, target opponent puts a card from their hand on top of their library.

Shadowfeed

Exile target card from a graveyard. You gain 3 life.

Witch's Cottage

({T}: Add {B}.)
Witch's Cottage enters tapped unless you control three or more other Swamps.
When Witch's Cottage enters untapped, you may put target creature card from your graveyard on top of your library.

Debt to the Kami

Choose one —
• Target opponent exiles a creature they control.
• Target opponent exiles an enchantment they control.

Bojuka Bog

Bojuka Bog enters tapped.
When Bojuka Bog enters, exile target player's graveyard.
{T}: Add {B}.

Unmake

Diabolic Edict

Target player sacrifices a creature of their choice.

Geth's Verdict

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

Duress

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

Sign in Blood

Target player draws two cards and loses 2 life.

Phyrexian Rager

When Phyrexian Rager enters, you draw a card and you lose 1 life.

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.)

Cuombajj Witches

{T}: Cuombajj Witches deals 1 damage to any target and 1 damage to any target of an opponent's choice.