Cabal Ritual

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

Bankrupt in Blood

As an additional cost to cast this spell, sacrifice two creatures.
Draw three cards.

Bubbling Muck

Until end of turn, whenever a player taps a Swamp for mana, that player adds an additional {B}.

Aphotic Wisps

Target creature becomes black and gains fear until end of turn. (It can't be blocked except by artifact creatures and/or black creatures.)
Draw a card.

Resourceful Return

Return target creature card from your graveyard to your hand. If you control an artifact, draw a card.

Armor of Shadows

Until end of turn, target creature gets +1/+0 and gains indestructible. (Damage and effects that say "destroy" don't destroy it.)

Forever Young

Put any number of target creature cards from your graveyard on top of your library.
Draw a card.

Corrupted Conviction

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

Mirrodin Avenged

Destroy target creature that was dealt damage this turn.
Draw a card.

Addle

Choose a color. Target player reveals their hand and you choose a card of that color from it. That player discards that card.

Demonic Tutor

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

You Are Already Dead

Altar's Reap

Devour in Shadow

Destroy target creature. It can't be regenerated. You lose life equal to that creature's toughness.

Bladebrand

Target creature gains deathtouch until end of turn.
Draw a card.

Diabolic Intent

As an additional cost to cast this spell, sacrifice a creature.
Search your library for a card, put that card into your hand, then shuffle.

Distress

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

Fandaniel, Telophoroi Ascian

Whenever you cast an instant or sorcery spell, surveil 1.
At the beginning of your end step, each opponent may sacrifice a nontoken creature of their choice. Each opponent who doesn't loses 2 life for each instant and sorcery card in your graveyard.

Cremate

Exile target card from a graveyard.
Draw a card.

Sign in Blood

Target player draws two cards and loses 2 life.

Appetite for Brains

Target opponent reveals their hand. You choose a card from it with mana value 4 or greater and exile that card.