Have

Everlasting Torment

Players can't gain life.
Damage can't be prevented.
All damage is dealt as though its source had wither. (A source with wither deals damage to creatures in the form of -1/-1 counters.)

Grim Poppet

This creature enters with three -1/-1 counters on it.
Remove a -1/-1 counter from this creature: Put a -1/-1 counter on another target creature.

Getting

Festering Mummy

When this creature dies, you may put a -1/-1 counter on target creature.

Soul Snuffers

When this creature enters, put a -1/-1 counter on each creature.

Assassin's Trophy

Destroy target permanent an opponent controls. Its controller may search their library for a basic land card, put it onto the battlefield, then shuffle.

Channeler Initiate

When this creature enters, put three -1/-1 counters on target creature you control.
{T}, Remove a -1/-1 counter from this creature: Add one mana of any color.

Fevered Suspicion

Each opponent exiles cards from the top of their library until they exile a nonland card. You may cast any number of spells from among those nonland cards without paying their mana costs.
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.)

Sol Ring

Ribbons

Aftermath (Cast this spell only from your graveyard. Then exile it.)
Each opponent loses X life.

Cut // Ribbons

Village Pillagers

Wither (This deals damage to creatures in the form of -1/-1 counters.)
When this creature enters, it deals 1 damage to each creature your opponents control.
Whenever a creature an opponent controls with a counter on it dies, you create a tapped Treasure token.

Destructive Revelry

Destroy target artifact or enchantment. Destructive Revelry deals 2 damage to that permanent's controller.

Persistent Constrictor

At the beginning of each opponent's upkeep, they lose 1 life and you put a -1/-1 counter on up to one target creature they control.
Persist (When this creature 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.)

Forest

Elixir of Immortality

{2}, {T}: You gain 5 life. Shuffle this artifact and your graveyard into their owner's library.

Banewhip Punisher

When this creature enters, you may put a -1/-1 counter on target creature.
{B}, Sacrifice this creature: Destroy target creature that has a -1/-1 counter on it.

Flourishing Defenses

Whenever a -1/-1 counter is put on a creature, you may create a 1/1 green Elf Warrior creature token.

Rampant Growth

Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Fume Spitter

Sacrifice this creature: Put a -1/-1 counter on target creature.

Black Sun's Zenith

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

Cultivate

Search your library for up to two basic land cards, reveal those cards, put one onto the battlefield tapped and the other into your hand, then shuffle.

Carnifex Demon

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

Mountain

Commander's Sphere

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

Naturalize

Bile-Vial Boggart

When this creature dies, put a -1/-1 counter on up to one target creature.

Lasting Tarfire

At the beginning of each end step, if you put a counter on a creature this turn, this enchantment deals 2 damage to each opponent.

Quillspike

{B/G}, Remove a -1/-1 counter from a creature you control: This creature gets +3/+3 until end of turn.

Crumbling Ashes

At the beginning of your upkeep, destroy target creature with a -1/-1 counter on it.

Breach the Multiverse

Each player mills ten cards. For each player, choose a creature or planeswalker card in that player's graveyard. Put those cards onto the battlefield under your control. Then each creature you control becomes a Phyrexian in addition to its other types.

Day of Black Sun

Each creature with mana value X or less loses all abilities until end of turn. Destroy those creatures.

Culling Ritual

Destroy each nonland permanent with mana value 2 or less. Add {B} or {G} for each permanent destroyed this way.

Putrefy

Destroy target artifact or creature. It can't be regenerated.

Kodama's Reach

Strategic Betrayal

Target opponent exiles a creature they control and their graveyard.

Grave Betrayal

Whenever a creature you don't control dies, return it to the battlefield under your control with an additional +1/+1 counter on it at the beginning of the next end step. That creature is a black Zombie in addition to its other colors and types.

Thelon's Chant

At the beginning of your upkeep, sacrifice this enchantment unless you pay {G}.
Whenever a player puts a Swamp onto the battlefield, this enchantment deals 3 damage to that player unless the player puts a -1/-1 counter on a creature they control.

Dauntless Scrapbot

When this creature enters, exile each opponent's graveyard. Create a Lander token. (It's an artifact with "{2}, {T}, Sacrifice this token: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.")

Tourach's Chant

At the beginning of your upkeep, sacrifice this enchantment unless you pay {B}.
Whenever a player puts a Forest onto the battlefield, this enchantment deals 3 damage to that player unless they put a -1/-1 counter on a creature they control.

Return to Nature

Choose one —
• Destroy target artifact.
• Destroy target enchantment.
• Exile target card from a graveyard.

Kulrath Knight

Flying
Wither (This deals damage to creatures in the form of -1/-1 counters.)
Creatures your opponents control with counters on them can't attack or block.

Blowfly Infestation

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

Living Death

Each player exiles all creature cards from their graveyard, then sacrifices all creatures they control, then puts all cards they exiled this way onto the battlefield.

Sakura-Tribe Elder

Sacrifice this creature: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Chain Reaction

Chain Reaction deals X damage to each creature, where X is the number of creatures on the battlefield.

Scar

Incarnation Technique

Demonstrate (When you cast this spell, you may copy it. If you do, choose an opponent to also copy it.)
Mill five cards, then return a creature card from your graveyard to the battlefield.

Rakdos Signet

Terminate

Destroy target creature. It can't be regenerated.

Aether Flash

Whenever a creature enters, this enchantment deals 2 damage to it.

Swamp

Nest of Scarabs

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

Arcane Signet

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

Solemn Simulacrum

When this creature enters, you may search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.
When this creature dies, you may draw a card.

Persist

Return target nonlegendary creature card from your graveyard to the battlefield with a -1/-1 counter on it.

Auntie Ool, Cursewretch

Ward—Blight 2. (To blight 2, a player puts two -1/-1 counters on a creature they control.)
Whenever one or more -1/-1 counters are put on a creature, draw a card if you control that creature. If you don't control it, its controller loses 1 life.

Soul Shatter

Each opponent sacrifices a creature or planeswalker with the greatest mana value among creatures and planeswalkers they control.

Necroskitter

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.

Obelisk Spider

Reach
Whenever this creature deals combat damage to a creature, put a -1/-1 counter on that creature.
Whenever you put one or more -1/-1 counters on a creature, each opponent loses 1 life and you gain 1 life.

Retribution

Choose two target creatures controlled by the same opponent. That player chooses and sacrifices one of those creatures. Put a -1/-1 counter on the other.

Harbinger of Night

At the beginning of your upkeep, put a -1/-1 counter on each creature.

Nameless Inversion

Changeling (This card is every creature type.)
Target creature gets +3/-3 and loses all creature types until end of turn.

Oft-Nabbed Goat

{1}: Draw a card. Gain control of this creature and put a -1/-1 counter on it. Only your opponents may activate this ability and only as a sorcery.
When this creature dies, if it had one or more -1/-1 counters on it, its owner draws that many cards and each other player loses that much life.

Morselhoarder

This creature enters with two -1/-1 counters on it.
Remove a -1/-1 counter from this creature: Add one mana of any color.