Fleshbag Marauder

When this creature enters, each player sacrifices a creature of their choice.

Braids, Arisen Nightmare

At the beginning of your end step, you may sacrifice an artifact, creature, enchantment, land, or planeswalker. If you do, each opponent may sacrifice a permanent of their choice that shares a card type with it. For each opponent who doesn't, that player loses 2 life and you draw a card.

Go for the Throat

Have

Dark Ritual

Withering Torment

Destroy target creature or enchantment. You lose 2 life.

Crypt Ghast

Extort (Whenever you cast a spell, you may pay {W/B}. If you do, each opponent loses 1 life and you gain that much life.)
Whenever you tap a Swamp for mana, add an additional {B}.

Jet Medallion

Black spells you cast cost {1} less to cast.

Maha, Its Feathers Night

Flying, trample
Ward—Discard a card.
Creatures your opponents control have base toughness 1.

Archfiend of Depravity

Flying
At the beginning of each opponent's end step, that player chooses up to two creatures they control, then sacrifices the rest.

Overkill

Target creature gets -0/-9999 until end of turn.

Demon's Disciple

When this creature enters, each player sacrifices a creature or planeswalker of their choice.

Massacre Girl

Menace
When Massacre Girl enters, each other creature gets -1/-1 until end of turn. Whenever a creature dies this turn, each creature other than Massacre Girl gets -1/-1 until end of turn.

Soul Shatter

Each opponent sacrifices a creature or planeswalker with the greatest mana value among creatures and planeswalkers they control.

The Masamune

As long as equipped creature is attacking, it has first strike and must be blocked if able.
Equipped creature has "If a creature dying causes a triggered ability of this creature or an emblem you own to trigger, that ability triggers an additional time."
Equip {2}

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control. It can attack and {T} no matter when it came under your control.)
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Infernal Grasp

Destroy target creature. You lose 2 life.

Sign in Blood

Target player draws two cards and loses 2 life.

Ophiomancer

At the beginning of each upkeep, if you control no Snakes, create a 1/1 black Snake creature token with deathtouch.

Gaius van Baelsar

When Gaius van Baelsar enters, choose one —
• Each player sacrifices a creature token of their choice.
• Each player sacrifices a nontoken creature of their choice.
• Each player sacrifices an enchantment of their choice.

Sheoldred's Edict

Choose one —
• Each opponent sacrifices a nontoken creature of their choice.
• Each opponent sacrifices a creature token of their choice.
• Each opponent sacrifices a planeswalker of their choice.

Phyrexian Arena

At the beginning of your upkeep, you draw a card and you lose 1 life.

Plaguecrafter

When this creature enters, each player sacrifices a creature or planeswalker of their choice. Each player who can't discards a card.

Lightning Greaves

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.)
Equip {0}

Gravelighter

Flying
When this creature enters, draw a card if a creature died this turn. Otherwise, each player sacrifices a creature of their choice.

Swift End

Destroy target creature or planeswalker. You lose 2 life. (Then exile this card. You may cast the creature later from exile.)

Murderous Rider

Lifelink
When this creature dies, put it on the bottom of its owner's library.

Murderous Rider // Swift End

Galian Beast

Trample, lifelink
When Galian Beast dies, return it to the battlefield tapped (front face up).

Vincent Valentine

Whenever a creature an opponent controls dies, put a number of +1/+1 counters on Vincent Valentine equal to that creature's power.
Whenever Vincent Valentine attacks, you may transform it.

Vincent Valentine // Galian Beast

Gray Merchant of Asphodel

When this creature 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.)

Massacre Wurm

When this creature enters, creatures your opponents control get -2/-2 until end of turn.
Whenever a creature an opponent controls dies, that player loses 2 life.

Feed the Swarm

Destroy target creature or enchantment an opponent controls. You lose life equal to that permanent's mana value.

Solemn Simulacrum

When this creature enters, you may search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.
When this creature dies, you may draw a card.

Shinryu, Transcendent Rival

Flying
As this creature transforms into Shinryu, choose an opponent.
Burning Chains — When the chosen player loses the game, you win the game.

Zenos yae Galvus

My First Friend — When Zenos yae Galvus enters, choose a creature an opponent controls. Until end of turn, creatures other than Zenos yae Galvus and the chosen creature get -2/-2.
When the chosen creature leaves the battlefield, transform Zenos yae Galvus.

Zenos yae Galvus // Shinryu, Transcendent Rival

Summon: Anima

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after IV.)
I, II, III — Pain — You draw a card and you lose 1 life.
IV — Oblivion — Each opponent sacrifices a creature of their choice and loses 3 life.
Menace

Dread Presence

Whenever a Swamp you control enters, choose one —
• You draw a card and you lose 1 life.
• This creature deals 2 damage to any target and you gain 2 life.

Morbid Opportunist

Whenever one or more other creatures die, draw a card. This ability triggers only once each turn.

Accursed Marauder

When this creature enters, each player sacrifices a nontoken creature of their choice.

Merciless Executioner

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.