Innocent Blood

Each player sacrifices a creature of their choice.

Ophiomancer

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

Mutilate

All creatures get -1/-1 until end of turn for each Swamp you control.

Fell Mire

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

Fell the Profane

Fell the Profane // Fell Mire

Sedgemoor Witch

Menace
Ward—Pay 3 life. (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays 3 life.)
Magecraft — Whenever you cast or copy an instant or sorcery spell, create a 1/1 black and green Pest creature token with "When this creature dies, you gain 1 life."

Power Word Kill

Destroy target non-Angel, non-Demon, non-Devil, non-Dragon creature.

Reanimate

Put target creature card from a graveyard onto the battlefield under your control. You lose life equal to its mana value.

Mind Twist

Target player discards X cards at random.

Boggart Bog

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

Boggart Trawler

When Boggart Trawler enters, exile target player's graveyard.

Boggart Trawler // Boggart Bog

Sign in Blood

Target player draws two cards and loses 2 life.

Long Goodbye

This spell can't be countered. (This includes by the ward ability.)
Destroy target creature or planeswalker with mana value 3 or less.

Erebos's Intervention

Choose one —
• Target creature gets -X/-X until end of turn. You gain X life.
• Exile up to twice X target cards from graveyards.

Emperor of Bones

At the beginning of combat on your turn, exile up to one target card from a graveyard.
{1}{B}: Adapt 2.
Whenever one or more +1/+1 counters are put on Emperor of Bones, put a creature card exiled with Emperor of Bones onto the battlefield under your control with a finality counter on it. It gains haste. Sacrifice it at the beginning of the next end step.

Shoot the Sheriff

Destroy target non-outlaw creature. (Assassins, Mercenaries, Pirates, Rogues, and Warlocks are outlaws. Everyone else is fair game.)

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.

Blackmail

Target player reveals three cards from their hand and you choose one of them. That player discards that card.

Insatiable Avarice

Spree (Choose one or more additional costs.)
+ {2} — Search your library for a card, then shuffle and put that card on top.
+ {B}{B} — Target player draws three cards and loses 3 life.

Disruptor Flute

Flash
As Disruptor Flute enters, choose a card name.
Spells with the chosen name cost {3} more to cast.
Activated abilities of sources with the chosen name can't be activated unless they're mana abilities.

Fell

Gatekeeper of Malakir

Kicker {B} (You may pay an additional {B} as you cast this spell.)
When this creature enters, if it was kicked, target player sacrifices a creature of their choice.

Imp's Mischief

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

Night's Whisper

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.

Bitter Triumph

As an additional cost to cast this spell, discard a card or pay 3 life.
Destroy target creature or planeswalker.

Profane Tutor

Suspend 2—{1}{B} (Rather than cast this card from your hand, pay {1}{B} and exile it with two time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost.)
Search your library for a card, put that card into your hand, then shuffle.

Oubliette

When Oubliette enters, target creature phases out until Oubliette leaves the battlefield. Tap that creature as it phases in this way. (Auras and Equipment phase out with it. While permanents are phased out, they're treated as though they don't exist.)

Sudden Edict

Split second (As long as this spell is on the stack, players can't cast spells or activate abilities that aren't mana abilities.)
Target player sacrifices a creature of their choice.

Chain of Smog

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