Have

Sign in Blood

Target player draws two cards and loses 2 life.

Pestilence

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

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.

Nihil Spellbomb

{T}, Sacrifice Nihil Spellbomb: Exile target player's graveyard.
When Nihil Spellbomb is put into a graveyard from the battlefield, you may pay {B}. If you do, draw a card.

Syphon Life

Target player loses 2 life and you gain 2 life.
Retrace (You may cast this card from your graveyard by discarding a land card in addition to paying its other costs.)

Cuombajj Witches

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

Gray Merchant of Asphodel

When Gray Merchant of Asphodel enters the battlefield, 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.)

Defile

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

Chainer's Edict

Target player sacrifices a creature.
Flashback {5}{B}{B} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Suffocating Fumes

Creatures your opponents control get -1/-1 until end of turn.
Cycling {2} ({2}, Discard this card: Draw a card.)

Okiba-Gang Shinobi

Ninjutsu {3}{B} ({3}{B}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
Whenever Okiba-Gang Shinobi deals combat damage to a player, that player discards two cards.

Cast Down

Duress

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

Bojuka Bog

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

Phyrexian Rager

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

Witch's Cottage

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

Crypt Rats

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

Unearth

Return target creature card with mana value 3 or less from your graveyard to the battlefield.
Cycling {2} ({2}, Discard this card: Draw a card.)

Divest

Target player reveals their hand. You choose an artifact or creature card from it. That player discards that card.

Thorn of the Black Rose

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

Reaping the Graves

Return target creature card from your graveyard to your hand.
Storm (When you cast this spell, copy it for each spell cast before it this turn. You may choose new targets for the copies.)

Chittering Rats

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

Crypt Incursion

Exile all creature cards from target player's graveyard. You gain 3 life for each card exiled this way.