Disciple of Perdition

When Disciple of Perdition dies, choose one. If you have exactly 13 life, you may choose both instead.
• You draw a card and you lose 1 life.
• Exile target opponent's graveyard. That player loses 1 life.

Bond of Agony

As an additional cost to cast this spell, pay X life.
Each other player loses X life.

Xathrid Necromancer

Whenever Xathrid Necromancer or another Human creature you control dies, create a tapped 2/2 black Zombie creature token.

Phyrexian Processor

As Phyrexian Processor enters, pay any amount of life.
{4}, {T}: Create an X/X black Phyrexian Minion creature token, where X is the life paid as Phyrexian Processor entered.

Exsanguinate

Each opponent loses X life. You gain life equal to the life lost this way.

Necrologia

Cast this spell only during your end step.
As an additional cost to cast this spell, pay X life.
Draw X cards.

Minion of the Wastes

Trample
As Minion of the Wastes enters, pay any amount of life.
Minion of the Wastes's power and toughness are each equal to the life paid as it entered.

Pain's Reward

Each player may bid life. You start the bidding with a bid of any number. In turn order, each player may top the high bid. The bidding ends if the high bid stands. The high bidder loses life equal to the high bid and draws four cards.

Font of Agonies

Whenever you pay life, put that many blood counters on Font of Agonies.
{1}{B}, Remove four blood counters from Font of Agonies: Destroy target creature.

Ormendahl, the Corrupter

Flying, trample, lifelink
Sacrifice another creature: Draw a card.

Jerren, Corrupted Bishop

Whenever Jerren, Corrupted Bishop enters or another nontoken Human you control dies, you lose 1 life and create a 1/1 white Human creature token.
{2}: Target Human you control gains lifelink until end of turn.
At the beginning of your end step, if you have exactly 13 life, you may pay {4}{B}{B}. If you do, transform Jerren.

Jerren, Corrupted Bishop // Ormendahl, the Corrupter

Toxic Deluge

As an additional cost to cast this spell, pay X life.
All creatures get -X/-X until end of turn.

Unspeakable Symbol

Pay 3 life: Put a +1/+1 counter on target creature.

Vilis, Broker of Blood

Flying
{B}, Pay 2 life: Target creature gets -1/-1 until end of turn.
Whenever you lose life, draw that many cards. (Damage causes loss of life.)

Shadow-Rite Priest

Other Clerics you control get +1/+1.
{3}{B}{B}, {T}, Sacrifice another Cleric: Search your library for a black creature card, put it onto the battlefield, then shuffle.

Black Market

Whenever a creature dies, put a charge counter on Black Market.
At the beginning of your first main phase, add {B} for each charge counter on Black Market.

K'rrik, Son of Yawgmoth

({B/P} can be paid with either {B} or 2 life.)
Lifelink
For each {B} in a cost, you may pay 2 life rather than pay that mana.
Whenever you cast a black spell, put a +1/+1 counter on K'rrik, Son of Yawgmoth.

Species Specialist

As Species Specialist enters, choose a creature type.
Whenever a creature of the chosen type dies, you may draw a card.

Greed

Doom Whisperer

Flying, trample
Pay 2 life: Surveil 2. (Look at the top two cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)

Wall of Blood

Defender (This creature can't attack.)
Pay 1 life: Wall of Blood gets +1/+1 until end of turn.

Dark Ritual

Peer into the Abyss

Target player draws cards equal to half the number of cards in their library and loses half their life. Round up each time.

Necropotence

Skip your draw step.
Whenever you discard a card, exile that card from your graveyard.
Pay 1 life: Exile the top card of your library face down. Put that card into your hand at the beginning of your next end step.

Bolas's Citadel

You may look at the top card of your library any time.
You may play lands and cast spells from the top of your library. If you cast a spell this way, pay life equal to its mana value rather than pay its mana cost.
{T}, Sacrifice ten nonland permanents: Each opponent loses 10 life.

Plague of Vermin

Starting with you, each player may pay any amount of life. Repeat this process until no one pays life. Each player creates a 1/1 black Rat creature token for each 1 life they paid this way.

Repay in Kind

Each player's life total becomes the lowest life total among all players.

Profane Transfusion

Two target players exchange life totals. You create an X/X colorless Horror artifact creature token, where X is the difference between those players' life totals.

Magus of the Mirror

{T}, Sacrifice Magus of the Mirror: Exchange life totals with target opponent. Activate only during your upkeep.

Pact Weapon

As long as Pact Weapon is attached to a creature, you don't lose the game for having 0 or less life.
Whenever equipped creature attacks, draw a card and reveal it. The creature gets +X/+X until end of turn and you lose X life, where X is that card's mana value.
Equip—Discard a card.