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

When Contagion Engine enters the battlefield, put a -1/-1 counter on each creature target player controls. {4}, {T}: Proliferate, then proliferate again. (Choose any number of permanents and/or players, then give each another counter of each kind already there. Then do it again.)

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

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.) Equip {0}

{T}: Add {C}{C}.

Flying Whenever you cycle or discard another card, put a -1/-1 counter on each creature your opponents control. Cycling {2} ({2}, Discard this card: Draw a card.)

{B}, {T}, Discard a card: Add {B}{B}{B}.

Flying Carnifex Demon enters the battlefield with two -1/-1 counters on it. {B}, Remove a -1/-1 counter from Carnifex Demon: Put a -1/-1 counter on each other creature.

Black creatures you control have wither. (They deal damage to creatures in the form of -1/-1 counters.)

{1}{B}, {T}, Discard a card: Create a 2/2 black Zombie creature token. Tap three untapped Zombies you control: You draw a card and you lose 1 life.

Skeletons you control and other Zombies you control get +1/+1 and have deathtouch.

When Gleaming Overseer enters the battlefield, amass Zombies 1. (Put a +1/+1 counter on an Army you control. It's also a Zombie. If you don't control an Army, create a 0/0 black Zombie Army creature token first.) Zombie tokens you control have hexproof and menace.

Flying {T}: Draw a card, then discard a card. {X}: Likeness Looter becomes a copy of target creature card in your graveyard with mana value X, except it has flying and this ability. Activate only as a sorcery.

Menace Creatures you control have wither. (They deal damage to creatures in the form of -1/-1 counters.) Whenever a creature an opponent controls dies, if its toughness was less than 1, draw a card.

Wither (This deals damage to creatures in the form of -1/-1 counters.) At the beginning of your upkeep, put a -1/-1 counter on each nonblack creature.

Intimidate (This creature can't be blocked except by artifact creatures and/or creatures that share a color with it.) Whenever a Human deals damage to you, destroy it. Other non-Human creatures you control get +1/+1 and have undying. (When a creature with undying dies, if it had no +1/+1 counters on it, return it to the battlefield under its owner's control with a +1/+1 counter on it.)

Wither (This deals damage to creatures in the form of -1/-1 counters.) Whenever a creature an opponent controls with a -1/-1 counter on it dies, you may return that card to the battlefield under your control.

Flying, trample Whenever an opponent searches their library, that player sacrifices a creature and loses 10 life. Whenever another creature dies, put a +1/+1 counter on Ob Nixilis, Unshackled.

Changeling Whenever you cast an instant or sorcery spell, if it targets one or more other permanents you control, create a token that's a copy of one of those permanents. When a spell or ability an opponent controls causes you to discard this card, create a token that's a copy of target permanent.

Flying When Overseer of the Damned enters the battlefield, you may destroy target creature. Whenever a nontoken creature an opponent controls dies, create a tapped 2/2 black Zombie creature token.

Whenever Psychic Frog deals combat damage to a player or planeswalker, draw a card. Discard a card: Put a +1/+1 counter on Psychic Frog. Exile three cards from your graveyard: Psychic Frog gains flying until end of turn.

Flying Morbid — At the beginning of each end step, if a creature died this turn, destroy target non-Demon creature.

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.) At the beginning of your upkeep, return target creature card from your graveyard to the battlefield. At the beginning of each opponent's upkeep, that player sacrifices a creature.

Whenever Sludge Monster enters the battlefield or attacks, put a slime counter on up to one other target creature. Non-Horror creatures with slime counters on them lose all abilities and have base power and toughness 2/2.

When Soul Snuffers enters the battlefield, put a -1/-1 counter on each creature.

Whenever Spitting Dilophosaurus enters the battlefield or attacks, put a -1/-1 counter on up to one target creature. Creatures your opponents control with -1/-1 counters on them can't block.

At the beginning of each end step, put a slime counter on each creature you don't control. Creatures you don't control get -1/-1 for each slime counter on them. Whenever a creature you don't control with a slime counter on it dies, create a 1/1 black Slug creature token. {U}{B}, Sacrifice a Slug: Draw a card.

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.)

{U}, {T}, Discard a card: Return target creature to its owner's hand.

Whenever a creature dies, if it had a -1/-1 counter on it, put a -1/-1 counter on target creature.

Each creature your opponents control is an Illusion in addition to its other types and has "When this creature becomes the target of a spell or ability, sacrifice it."

Enchant creature you control At the beginning of your upkeep, create a token that's a copy of enchanted creature, except the token is 1/1. When enchanted creature dies, if that creature was a Horror, return Endless Evil to its owner's hand.

Whenever you put one or more -1/-1 counters on a creature, create that many 1/1 black Insect creature tokens.

Counter target noncreature spell. Its controller creates two Treasure tokens. (They're artifacts with "{T}, Sacrifice this artifact: Add one mana of any color.")

Add {B}{B}{B}.

Draw two cards, then discard a card. You gain life equal to the number of cards you've discarded this turn. Jump-start (You may cast this card from your graveyard by discarding a card in addition to paying its other costs. Then exile this card.)

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

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

Creatures your opponents control have base power and toughness 0/1 until end of turn.

Put a -1/-1 counter on target creature, then proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Counter target instant or sorcery spell. Transmute {1}{U}{U} ({1}{U}{U}, Discard this card: Search your library for a card with the same mana value as this card, reveal it, put it into your hand, then shuffle. Transmute only as a sorcery.)

Until end of turn, each creature target player controls loses all abilities and becomes a blue Frog with base power and toughness 1/1.

Destroy target creature. It can't be regenerated. Its controller creates a 3/3 green Ape creature token.

Storm (When you cast this spell, copy it for each spell cast before it this turn.) Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Return target nonland permanent to its owner's hand. If that permanent had mana value 3 or less, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Choose one — • Each opponent sacrifices a nontoken creature. • Each opponent sacrifices a creature token. • Each opponent sacrifices a planeswalker.

Split second (As long as this spell is on the stack, players can't cast spells or activate abilities that aren't mana abilities.) Until end of turn, creatures target player controls lose all abilities and have base power and toughness 0/2.

Counter target enchantment, instant, or sorcery spell. Its controller creates a 2/2 blue Bird creature token with flying.

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

Drowned Catacomb enters the battlefield tapped unless you control an Island or a Swamp. {T}: Add {U} or {B}.

({T}: Add {U}.)

Morphic Pool enters the battlefield tapped unless you have two or more opponents. {T}: Add {U} or {B}.

{T}, Pay 1 life, Sacrifice Polluted Delta: Search your library for an Island or Swamp card, put it onto the battlefield, then shuffle.

Shipwreck Marsh enters the battlefield tapped unless you control two or more other lands. {T}: Add {U} or {B}.

{T}: Add {C}. {U/B}, {T}: Add {U}{U}, {U}{B}, or {B}{B}.

({T}: Add {B}.)

Create thirteen tapped 2/2 black Zombie creature tokens. Flashback {7}{B}{B}{B} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Put X -1/-1 counters on each creature. Shuffle Black Sun's Zenith into its owner's library.

Search your library for up to three creature cards, put them into your graveyard, then shuffle.

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

Target creature gets -4/-4 until end of turn. Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

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

Search your library for a card, put that card into your hand, then shuffle. You lose 3 life.

Put a -1/-1 counter on target creature, two -1/-1 counters on another target creature, and three -1/-1 counters on a third target creature.

Until your next turn, creatures target player controls have base power and toughness 1/1. Flashback {3}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)