Staff of the Death Magus

Whenever you cast a black spell or a Swamp you control enters, you gain 1 life.

Fell Beast of Mordor

Flying
Devour 1 (As this enters, you may sacrifice any number of creatures. This creature enters with that many +1/+1 counters on it.)
Whenever Fell Beast of Mordor enters or attacks, target opponent loses X life and you gain X life, where X is the number of +1/+1 counters on it.

Dread Return

Return target creature card from your graveyard to the battlefield.
Flashback—Sacrifice three creatures. (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Consuming Corruption

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

Morbid Opportunist

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

Greed

Noxious Gearhulk

Menace
When Noxious Gearhulk enters, you may destroy another target creature. If a creature is destroyed this way, you gain life equal to its toughness.

Exsanguinate

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

Demon's Horn

Whenever a player casts a black spell, you may gain 1 life.

Blood Speaker

At the beginning of your upkeep, you may sacrifice Blood Speaker. If you do, search your library for a Demon card, reveal that card, put it into your hand, then shuffle.
Whenever a Demon enters under your control, return Blood Speaker from your graveyard to your hand.

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.

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control.)
Equip {1}

Phyrexian Arena

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

Victimize

Choose two target creature cards in your graveyard. Sacrifice a creature. If you do, return the chosen cards to the battlefield tapped.

Prism Ring

As Prism Ring enters, choose a color.
Whenever you cast a spell of the chosen color, you gain 1 life.

Damnation

Destroy all creatures. They can't be regenerated.

Persist

Return target nonlegendary creature card from your graveyard to the battlefield with a -1/-1 counter on it.

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.

Bloodletter of Aclazotz

Flying
If an opponent would lose life during your turn, they lose twice that much life instead. (Damage causes loss of life.)

Veinwitch Coven

Menace
Whenever you gain life, you may pay {B}. If you do, return target creature card from your graveyard to your hand.

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.

Ad Nauseam

Reveal the top card of your library and put that card into your hand. You lose life equal to its mana value. You may repeat this process any number of times.

Magus of the Mirror

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

Crypt Incursion

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

Tendrils of Agony

Target player loses 2 life and you gain 2 life.
Storm (When you cast this spell, copy it for each spell cast before it this turn. You may choose new targets for the copies.)

Dark Tutelage

At the beginning of your upkeep, reveal the top card of your library and put that card into your hand. You lose life equal to its mana value.

Damnable Pact

Target player draws X cards and loses X life.

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.

Elixir of Immortality

{2}, {T}: You gain 5 life. Shuffle Elixir of Immortality and your graveyard into their owner's library.

Sol Ring

Decree of Pain

Destroy all creatures. They can't be regenerated. Draw a card for each creature destroyed this way.
Cycling {3}{B}{B} ({3}{B}{B}, Discard this card: Draw a card.)
When you cycle Decree of Pain, all creatures get -2/-2 until end of turn.

Murder

Fake Your Own Death

Until end of turn, target creature gets +2/+0 and gains "When this creature dies, return it to the battlefield tapped under its owner's control and you create a Treasure token." (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Nighthawk Scavenger

Flying, deathtouch, lifelink
Nighthawk Scavenger's power is equal to 1 plus the number of card types among cards in your opponents' graveyards.

Grim Servant

Menace
When Grim Servant enters, search your library for a card with mana value less than or equal to your devotion to black, reveal it, put it into your hand, then shuffle. You lose 3 life. (Each {B} in the mana costs of permanents you control counts toward your devotion to black.)

Dark Ritual

Supernatural Stamina

Until end of turn, target creature gets +2/+0 and gains "When this creature dies, return it to the battlefield tapped under its owner's control."

Sign in Blood

Target player draws two cards and loses 2 life.

Give In to Violence

Target creature gets +2/+2 and gains lifelink until end of turn.

Barren Moor

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

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.)

Asmodeus the Archfiend

Binding Contract — If you would draw a card, exile the top card of your library face down instead.
{B}{B}{B}: Draw seven cards.
{B}: Return all cards exiled with Asmodeus the Archfiend to their owner's hand and you lose that much life.

Mask of Griselbrand

Equipped creature has flying and lifelink.
Whenever equipped creature dies, you may pay X life, where X is its power. If you do, draw X cards.
Equip {3}

Sangromancer

Flying
Whenever a creature an opponent controls dies, you may gain 3 life.
Whenever an opponent discards a card, you may gain 3 life.

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.

Blood Pact

Feed the Swarm

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

Nullpriest of Oblivion

Kicker {3}{B}
Menace, lifelink
When Nullpriest of Oblivion enters, if it was kicked, return target creature card from your graveyard to the battlefield.

Swamp

Profane Command

Choose two —
• Target player loses X life.
• Return target creature card with mana value X or less from your graveyard to the battlefield.
• Target creature gets -X/-X until end of turn.
• Up to X target creatures gain fear until end of turn. (They can't be blocked except by artifact creatures and/or black creatures.)

Read the Bones

Scry 2, then draw two cards. You lose 2 life. (To scry 2, look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Chainer, Dementia Master

All Nightmares get +1/+1.
{B}{B}{B}, Pay 3 life: Put target creature card from a graveyard onto the battlefield under your control. That creature is black and is a Nightmare in addition to its other creature types.
When Chainer, Dementia Master leaves the battlefield, exile all Nightmares.

Enduring Tenacity

Whenever you gain life, target opponent loses that much life.
When Enduring Tenacity dies, if it was a creature, return it to the battlefield under its owner's control. It's an enchantment. (It's not a creature.)

Starving Revenant

When Starving Revenant enters, surveil 2. Then for each card you put on top of your library, you draw a card and you lose 3 life.
Descend 8 — Whenever you draw a card, if there are eight or more permanent cards in your graveyard, target opponent loses 1 life and you gain 1 life.

Activated Sleeper

Flash
You may have Activated Sleeper enter as a copy of any creature card in a graveyard that was put there from the battlefield this turn, except it's a Phyrexian in addition to its other types.

Viscera Seer

Sacrifice a creature: Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Alhammarret's Archive

If you would gain life, you gain twice that much life instead.
If you would draw a card except the first one you draw in each of your draw steps, draw two cards instead.

Mortuary Mire

Mortuary Mire enters tapped.
When Mortuary Mire enters, you may put target creature card from your graveyard on top of your library.
{T}: Add {B}.

Gollum, Obsessed Stalker

Skulk (This creature can't be blocked by creatures with greater power.)
At the beginning of your end step, each opponent dealt combat damage this game by a creature named Gollum, Obsessed Stalker loses life equal to the amount of life you gained this turn.

Blood Tithe

Each opponent loses 3 life. You gain life equal to the life lost this way.

Venomcrawler

Lifelink
Devourer of Souls — Whenever another creature dies, put a +1/+1 counter on Venomcrawler.

Exquisite Blood

Whenever an opponent loses life, you gain that much life.

Nowhere to Run

Flash
When Nowhere to Run enters, target creature an opponent controls gets -3/-3 until end of turn.
Creatures your opponents control can be the targets of spells and abilities as though they didn't have hexproof. Ward abilities of those creatures don't trigger.

Feign Death

Until end of turn, target creature gains "When this creature dies, return it to the battlefield tapped under its owner's control with a +1/+1 counter on it."

Demonlord Belzenlok

Flying, trample
When Demonlord Belzenlok enters, exile cards from the top of your library until you exile a nonland card, then put that card into your hand. If the card's mana value is 4 or greater, repeat this process. Demonlord Belzenlok deals 1 damage to you for each card put into your hand this way.

Diresight

Surveil 2, then draw two cards. You lose 2 life. (To 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.)

Rune-Scarred Demon

Flying
When Rune-Scarred Demon enters, search your library for a card, put it into your hand, then shuffle.

Nighthaze

Target creature gains swampwalk until end of turn. (It can't be blocked as long as defending player controls a Swamp.)
Draw a card.

Battle-Rage Blessing

Target creature gains deathtouch and indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)