Demonic Tutor

Search your library for a card, put that card into your hand, then shuffle.

Overeager Apprentice

Discard a card, Sacrifice Overeager Apprentice: Add {B}{B}{B}.

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.

Sign in Blood

Target player draws two cards and loses 2 life.

Lotus Petal

{T}, Sacrifice Lotus Petal: Add one mana of any color.

Cabal Ritual

Add {B}{B}{B}.
Threshold — Add {B}{B}{B}{B}{B} instead if seven or more cards are in your graveyard.

Sacrifice

As an additional cost to cast this spell, sacrifice a creature.
Add an amount of {B} equal to the sacrificed creature's mana value.

Lich's Mirror

If you would lose the game, instead shuffle your hand, your graveyard, and all permanents you own into your library, then draw seven cards and your life total becomes 20.

Culling the Weak

As an additional cost to cast this spell, sacrifice a creature.
Add {B}{B}{B}{B}.

Deadly Rollick

If you control a commander, you may cast this spell without paying its mana cost.
Exile target creature.

Cut Down

Destroy target creature with total power and toughness 5 or less.

Blood Pet

Inquisition of Kozilek

Target player reveals their hand. You choose a nonland card from it with mana value 3 or less. That player discards that card.

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.)

Skirge Familiar

Dark Confidant

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.

Fatal Push

Destroy target creature if it has mana value 2 or less.
Revolt — Destroy that creature if it has mana value 4 or less instead if a permanent you controlled left the battlefield this turn.

Grief

Menace
When Grief enters, target opponent reveals their hand. You choose a nonland card from it. That player discards that card.
Evoke—Exile a black card from your hand.

Village Rites

As an additional cost to cast this spell, sacrifice a creature.
Draw two cards.

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.

Professor Onyx

Magecraft — Whenever you cast or copy an instant or sorcery spell, each opponent loses 2 life and you gain 2 life.
+1: You lose 1 life. Look at the top three cards of your library. Put one of them into your hand and the rest into your graveyard.
−3: Each opponent sacrifices a creature with the greatest power among creatures that player controls.
−8: Each opponent may discard a card. If they don't, they lose 3 life. Repeat this process six more times.

Yawgmoth's Bargain

Skip your draw step.
Pay 1 life: Draw a card.

Dark Ritual

Imp's Mischief

Change the target of target spell with a single target. You lose life equal to that spell's mana value.

Boseiju, Who Shelters All

Boseiju, Who Shelters All enters tapped.
{T}, Pay 2 life: Add {C}. If that mana is spent on an instant or sorcery spell, that spell can't be countered.

Conqueror's Flail

Equipped creature gets +1/+1 for each color among permanents you control.
As long as Conqueror's Flail is attached to a creature, your opponents can't cast spells during your turn.
Equip {2}

Defense Grid

Each spell costs {3} more to cast except during its controller's turn.

Lich's Tomb

You don't lose the game for having 0 or less life.
Whenever you lose life, sacrifice a permanent for each 1 life you lost. (Damage causes loss of life.)

Dauthi Voidwalker

Shadow (This creature can block or be blocked by only creatures with shadow.)
If a card would be put into an opponent's graveyard from anywhere, instead exile it with a void counter on it.
{T}, Sacrifice Dauthi Voidwalker: Choose an exiled card an opponent owns with a void counter on it. You may play it this turn without paying its mana cost.

Lich

As Lich enters, you lose life equal to your life total.
You don't lose the game for having 0 or less life.
If you would gain life, draw that many cards instead.
Whenever you're dealt damage, sacrifice that many nontoken permanents. If you can't, you lose the game.
When Lich is put into a graveyard from the battlefield, you lose the game.

Jet Medallion

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

Rain of Filth

Until end of turn, lands you control gain "Sacrifice this land: Add {B}."

Dismember

({B/P} can be paid with either {B} or 2 life.)
Target creature gets -5/-5 until end of turn.

Ancient Tomb

{T}: Add {C}{C}. Ancient Tomb deals 2 damage to you.

Yawgmoth's Will

Until end of turn, you may play lands and cast spells from your graveyard.
If a card would be put into your graveyard from anywhere this turn, exile that card instead.

Blood Celebrant

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

Lake of the Dead

If Lake of the Dead would enter, sacrifice a Swamp instead. If you do, put Lake of the Dead onto the battlefield. If you don't, put it into its owner's graveyard.
{T}: Add {B}.
{T}, Sacrifice a Swamp: Add {B}{B}{B}{B}.

Thoughtseize

Target player reveals their hand. You choose a nonland card from it. That player discards that card. You lose 2 life.

Chain of Smog

Target player discards two cards. That player may copy this spell and may choose a new target for that copy.

Deadly Dispute

As an additional cost to cast this spell, sacrifice an artifact or creature.
Draw two cards and create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Opposition Agent

Flash
You control your opponents while they're searching their libraries.
While an opponent is searching their library, they exile each card they find. You may play those cards for as long as they remain exiled, and you may spend mana as though it were mana of any color to cast them.

Cabal Coffers

{2}, {T}: Add {B} for each Swamp you control.

Grim Monolith

Grim Monolith doesn't untap during your untap step.
{T}: Add {C}{C}{C}.
{4}: Untap Grim Monolith.

Vampiric Tutor

Search your library for a card, then shuffle and put that card on top. You lose 2 life.