Ambulatory Edifice

When this creature enters, you may pay 2 life. When you do, target creature gets -1/-1 until end of turn.

Bloodstained Mire

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

Temple of Aclazotz

(Transforms from Arguel's Blood Fast.)
{T}: Add {B}.
{T}, Sacrifice a creature: You gain life equal to the sacrificed creature's toughness.

Arguel's Blood Fast

{1}{B}, Pay 2 life: Draw a card.
At the beginning of your upkeep, if you have 5 or less life, you may transform Arguel's Blood Fast.

Arguel's Blood Fast // Temple of Aclazotz

Anrakyr the Traveller

Lord of the Pyrrhian Legions — Whenever Anrakyr the Traveller attacks, you may cast an artifact spell from your hand or graveyard by paying life equal to its mana value rather than paying its mana cost.

Bloodtracker

Flying
{B}, Pay 2 life: Put a +1/+1 counter on this creature.
When this creature leaves the battlefield, draw a card for each +1/+1 counter on it.

Blood Celebrant

{B}, Pay 1 life: Add one mana of any color.

Bond of Agony

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

Arrogant Poet

Whenever this creature attacks, you may pay 2 life. If you do, it gains flying until end of turn.

Agadeem, the Undercrypt

As this land enters, you may pay 3 life. If you don't, it enters tapped.
{T}: Add {B}.

Agadeem's Awakening

Return from your graveyard to the battlefield any number of target creature cards that each have a different mana value X or less.

Agadeem's Awakening // Agadeem, the Undercrypt

Circle of Affliction

As this enchantment enters, choose a color.
Whenever a source of the chosen color deals damage to you, you may pay {1}. If you do, target player loses 1 life and you gain 1 life.

Bloodsoaked Altar

{T}, Pay 2 life, Discard a card, Sacrifice a creature: Create a 5/5 black Demon creature token with flying. Activate only as a sorcery.

Cruel Sadist

{B}, {T}, Pay 1 life: Put a +1/+1 counter on this creature.
{2}{B}, {T}, Remove X +1/+1 counters from this creature: It deals X damage to target creature.

Carnophage

At the beginning of your upkeep, tap this creature unless you pay 1 life.

Aetherflux Reservoir

Whenever you cast a spell, you gain 1 life for each spell you've cast this turn.
Pay 50 life: This artifact deals 50 damage to any target.

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.)

Cutthroat Contender

Pay 1 life: This creature gets +1/+0 until end of turn. Activate only once each turn.

Arco-Flagellant

Squad {2} (As an additional cost to cast this spell, you may pay {2} any number of times. When this creature enters, create that many tokens that are copies of it.)
This creature can't block.
Endurant — Pay 3 life: This creature gains indestructible until end of turn.

Blood Clock

At the beginning of each player's upkeep, that player returns a permanent they control to its owner's hand unless they pay 2 life.

Book of Rass

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.