Mortician Beetle

Whenever a player sacrifices a creature, you may put a +1/+1 counter on Mortician Beetle.

Virus Beetle

When Virus Beetle enters, each opponent discards a card.

Fumulus, the Infestation

Flying, deathtouch
Whenever a player sacrifices a nontoken creature, create a 1/1 black Insect creature token with flying.
Whenever an Insect, Leech, Slug, or Worm you control attacks, defending player loses 1 life and you gain 1 life.

Bag of Devouring

Whenever you sacrifice another nontoken artifact or creature, exile it.
{2}, {T}, Sacrifice another artifact or creature: Draw a card.
{3}, {T}, Sacrifice Bag of Devouring: Roll a d10. Return up to X cards from among cards exiled with Bag of Devouring to their owners' hands, where X is the result.

Leeching Lurker

Lifelink
Nightbound (If a player casts at least two spells during their own turn, it becomes day next turn.)

Curse of Leeches

Enchant player
As this permanent transforms into Curse of Leeches, attach it to a player.
At the beginning of enchanted player's upkeep, they lose 1 life and you gain 1 life.
Daybound (If a player casts no spells during their own turn, it becomes night next turn.)

Curse of Leeches // Leeching Lurker

Nantuko Husk

Sacrifice a creature: Nantuko Husk gets +2/+2 until end of turn.

Bane of the Living

Morph {X}{B}{B} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)
When Bane of the Living is turned face up, all creatures get -X/-X until end of turn.

Hex Parasite

{X}{B/P}: Remove up to X counters from target permanent. For each counter removed this way, Hex Parasite gets +1/+0 until end of turn. ({B/P} can be paid with either {B} or 2 life.)

Hagra Broodpit

Hagra Broodpit enters tapped.
{T}: Add {B}.

Hagra Mauling

This spell costs {1} less to cast if an opponent controls no basic lands.
Destroy target creature.

Hagra Mauling // Hagra Broodpit

Command Tower

{T}: Add one mana of any color in your commander's color identity.

Carrion

As an additional cost to cast this spell, sacrifice a creature.
Create X 0/1 black Insect creature tokens, where X is the sacrificed creature's power.

Devouring Swarm

Flying
Sacrifice a creature: Devouring Swarm gets +1/+1 until end of turn.

Sol Ring

Swarm of Bloodflies

Flying
Swarm of Bloodflies enters with two +1/+1 counters on it.
Whenever another creature dies, put a +1/+1 counter on Swarm of Bloodflies.

Brain Weevil

Intimidate (This creature can't be blocked except by artifact creatures and/or creatures that share a color with it.)
Sacrifice Brain Weevil: Target player discards two cards. Activate only as a sorcery.

Charcoal Diamond

Charcoal Diamond enters tapped.
{T}: Add {B}.

Primordial Gnawer

When Primordial Gnawer dies, discover 3. (Exile cards from the top of your library until you exile a nonland card with mana value 3 or less. Cast it without paying its mana cost or put it into your hand. Put the rest on the bottom in a random order.)

Armillary Sphere

{2}, {T}, Sacrifice Armillary Sphere: Search your library for up to two basic land cards, reveal them, put them into your hand, then shuffle.

Deadly Grub

Vanishing 3 (This creature enters with three time counters on it. At the beginning of your upkeep, remove a time counter from it. When the last is removed, sacrifice it.)
When Deadly Grub dies, if it had no time counters on it, create a 6/1 green Insect creature token with shroud. (It can't be the target of spells or abilities.)

Canoptek Scarab Swarm

Flying
Feeder Mandibles — When Canoptek Scarab Swarm enters, exile target player's graveyard. For each artifact or land card exiled this way, create a 1/1 colorless Insect artifact creature token with flying.

Magnifying Glass

{T}: Add {C}.
{4}, {T}: Investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Hidden Necropolis

Hidden Necropolis enters tapped.
{T}: Add {B}.
{4}{B}, {T}, Sacrifice Hidden Necropolis: Discover 4. Activate only as a sorcery. (Exile cards from the top of your library until you exile a nonland card with mana value 4 or less. Cast it without paying its mana cost or put it into your hand. Put the rest on the bottom in a random order.)

Stirge

Flying
Stirge can't block.
Blood Drain — {1}{B}, Pay 1 life, Sacrifice Stirge: Draw 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}

Rot Farm Mortipede

Whenever one or more creature cards leave your graveyard, Rot Farm Mortipede gets +1/+0 and gains menace and lifelink until end of turn.

Dross Hopper

Sacrifice a creature: Dross Hopper gains flying until end of turn.

Everglades

Everglades enters tapped.
When Everglades enters, sacrifice it unless you return an untapped Swamp you control to its owner's hand.
{T}: Add {C}{B}.

Victimize

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

Bone Shards

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

Swamp

Blood Fountain

When Blood Fountain enters, create a Blood token. (It's an artifact with "{1}, {T}, Discard a card, Sacrifice this artifact: Draw a card.")
{3}{B}, {T}, Sacrifice Blood Fountain: Return up to two target creature cards from your graveyard to your hand.

Thought Vessel

You have no maximum hand size.
{T}: Add {C}.

Bojuka Bog

Bojuka Bog enters tapped.
When Bojuka Bog enters, exile target player's graveyard.
{T}: Add {B}.

Gauntlet of Power

As Gauntlet of Power enters, choose a color.
Creatures of the chosen color get +1/+1.
Whenever a basic land is tapped for mana of the chosen color, its controller adds an additional one mana of that color.

Pestilent Souleater

{B/P}: Pestilent Souleater gains infect until end of turn. ({B/P} can be paid with either {B} or 2 life. A creature with infect deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

Barren Moor

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

All Is Dust

Each player sacrifices all permanents they control that are one or more colors.

Diabolic Edict

Castle Locthwain

Castle Locthwain enters tapped unless you control a Swamp.
{T}: Add {B}.
{1}{B}{B}, {T}: Draw a card, then you lose life equal to the number of cards in your hand.

Morkrut Necropod

Menace (This creature can't be blocked except by two or more creatures.)
Whenever Morkrut Necropod attacks or blocks, sacrifice another creature or land.

Blood Divination

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

Chainer's Edict

Target player sacrifices a creature.
Flashback {5}{B}{B} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Come Back Wrong

Destroy target creature. If a creature card is put into a graveyard this way, return it to the battlefield under your control. Sacrifice it at the beginning of your next end step.

Circuit Mender

When Circuit Mender enters, you gain 2 life.
When Circuit Mender leaves the battlefield, draw a card.

Withering Torment

Destroy target creature or enchantment. You lose 2 life.

Squelching Leeches

Squelching Leeches's power and toughness are each equal to the number of Swamps you control.

Bad Moon

Murder

Barter in Blood

Exotic Orchard

{T}: Add one mana of any color that a land an opponent controls could produce.

Wriggling Grub

When Wriggling Grub dies, create two 1/1 black and green Worm creature tokens.

Grave Pact

Whenever a creature you control dies, each other player sacrifices a creature.

Innocent Blood

Blasphemous Edict

You may pay {B} rather than pay this spell's mana cost if there are thirteen or more creatures on the battlefield.
Each player sacrifices thirteen creatures of their choice.

Annihilating Glare

As an additional cost to cast this spell, pay {4} or sacrifice an artifact or creature.
Destroy target creature or planeswalker.

Consuming Vapors

Target player sacrifices a creature. You gain life equal to that creature's toughness.
Rebound (If you cast this spell from your hand, exile it as it resolves. At the beginning of your next upkeep, you may cast this card from exile without paying its mana cost.)

Agent of the Iron Throne

Commander creatures you own have "Whenever an artifact or creature you control is put into a graveyard from the battlefield, each opponent loses 1 life."

Arcane Signet

Blightbeetle

Protection from green (This creature can't be blocked, targeted, dealt damage, enchanted, or equipped by anything green.)
Creatures your opponents control can't have +1/+1 counters put on them.

Blessing of Leeches

Flash
Enchant creature
At the beginning of your upkeep, you lose 1 life.
{0}: Regenerate enchanted creature.

Extract a Confession

As an additional cost to cast this spell, you may collect evidence 6. (Exile cards with total mana value 6 or greater from your graveyard.)
Each opponent sacrifices a creature. If evidence was collected, instead each opponent sacrifices a creature with the greatest power among creatures they control.

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice Mind Stone: Draw a card.

Altar's Reap

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

Alchemist's Vial

When Alchemist's Vial enters, draw a card.
{1}, {T}, Sacrifice Alchemist's Vial: Target creature can't attack or block this turn.

Bone Splinters

As an additional cost to cast this spell, sacrifice a creature.
Destroy target creature.

Huskburster Swarm

This spell costs {1} less to cast for each creature card you own in exile and in your graveyard.
Menace, deathtouch

Wretched Bonemass

Wretched Bonemass's power and toughness are each equal to the total power of the exiled cards used to craft it.
Wretched Bonemass has flying as long as an exiled card used to craft it has flying. The same is true for first strike, double strike, deathtouch, haste, hexproof, indestructible, lifelink, menace, protection, reach, trample, and vigilance.

Altar of the Wretched

When Altar of the Wretched enters, you may sacrifice a nontoken creature. If you do, draw X cards, then mill X cards, where X is that creature's power.
Craft with one or more creatures {2}{B}{B}
{2}{B}: Return Altar of the Wretched from your graveyard to your hand.

Altar of the Wretched // Wretched Bonemass

Commander's Sphere

{T}: Add one mana of any color in your commander's color identity.
Sacrifice Commander's Sphere: Draw a card.

Dead Drop

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)
Target player sacrifices two creatures.

Henrika, Infernal Seer

Flying, deathtouch, lifelink
{1}{B}{B}: Each creature you control with flying, deathtouch, and/or lifelink gets +1/+0 until end of turn.

Henrika Domnathi

Flying
At the beginning of combat on your turn, choose one that hasn't been chosen —
• Each player sacrifices a creature.
• You draw a card and you lose 1 life.
• Transform Henrika Domnathi.

Henrika Domnathi // Henrika, Infernal Seer

Mire in Misery

Each opponent sacrifices a creature or enchantment.

Stinging Cave Crawler

Deathtouch
Descend 4 — Whenever Stinging Cave Crawler attacks, if there are four or more permanent cards in your graveyard, you draw a card and you lose 1 life.

Call to the Grave

At the beginning of each player's upkeep, that player sacrifices a non-Zombie creature.
At the beginning of the end step, if no creatures are on the battlefield, sacrifice Call to the Grave.