Sinister Gnarlbark

At the beginning of your end step, draw a card and blight 1. (Put a -1/-1 counter on a creature you control.)

Massacre Girl, Known Killer

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.

Decimator Beetle

When this creature enters, put a -1/-1 counter on target creature you control.
Whenever this creature attacks, remove a -1/-1 counter from target creature you control and put a -1/-1 counter on up to one target creature defending player controls.

Creakwood Safewright

This creature enters with three -1/-1 counters on it.
At the beginning of your end step, if there is an Elf card in your graveyard and this creature has a -1/-1 counter on it, remove a -1/-1 counter from this creature.

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.

Rakdos Signet

Golgari Signet

Black Sun's Zenith

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

Gruul Guildgate

This land enters tapped.
{T}: Add {R} or {G}.

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.

Temple of the False God

{T}: Add {C}{C}. Activate only if you control five or more lands.

Nightmare Sower

Flying, lifelink
Whenever you cast a spell during an opponent's turn, put a -1/-1 counter on up to one target creature.

Gnarlbark Elm

This creature enters with two -1/-1 counters on it.
{2}{B}, Remove two counters from this creature: Target creature gets -2/-2 until end of turn. Activate only as a sorcery.

Instill Infection

Put a -1/-1 counter on target creature.
Draw a card.

Hapatra's Mark

Target creature you control gains hexproof until end of turn. Remove all -1/-1 counters from it. (A creature with hexproof can't be the target of spells or abilities your opponents control.)

Bile-Vial Boggart

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

Heirloom Auntie

This creature enters with two -1/-1 counters on it.
Whenever another creature you control dies, surveil 1, then remove a -1/-1 counter from this creature. (To surveil 1, look at the top card of your library. You may put it into your graveyard.)

The Scorpion God

Whenever a creature with a -1/-1 counter on it dies, draw a card.
{1}{B}{R}: Put a -1/-1 counter on another target creature.
When The Scorpion God dies, return it to its owner's hand at the beginning of the next end step.

Hapatra, Vizier of Poisons

Whenever Hapatra deals combat damage to a player, you may put a -1/-1 counter on target creature.
Whenever you put one or more -1/-1 counters on a creature, create a 1/1 green Snake creature token with deathtouch.

Gruul Turf

This land enters tapped.
When this land enters, return a land you control to its owner's hand.
{T}: Add {R}{G}.

Festering Mummy

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

Golgari Guildgate

This land enters tapped.
{T}: Add {B} or {G}.

Archfiend of Ifnir

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.)

Talisman of Resilience

{T}: Add {C}.
{T}: Add {B} or {G}. This artifact deals 1 damage to you.

Rakdos Carnarium

This land enters tapped.
When this land enters, return a land you control to its owner's hand.
{T}: Add {B}{R}.

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.

Exemplar of Strength

When this creature enters, put three -1/-1 counters on target creature you control.
Whenever this creature attacks, remove a -1/-1 counter from it. If you do, you gain 1 life.

Darkness Descends

Temple of Abandon

This land enters tapped.
When this land enters, scry 1. (Look at the top card of your library. You may put that card on the bottom.)
{T}: Add {R} or {G}.

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.

The Reaper, King No More

When The Reaper enters, put a -1/-1 counter on each of up to two target creatures.
Whenever a creature an opponent controls with a -1/-1 counter on it dies, you may put that card onto the battlefield under your control. Do this only once each turn.

Blight Rot

Put four -1/-1 counters on target creature.

Commander's Sphere

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

Phyrexian Arena

At the beginning of your upkeep, you draw a card and you lose 1 life.

Blowfly Infestation

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

Blur of Blades

Put a -1/-1 counter on target creature. Blur of Blades deals 2 damage to that creature's controller.

Talisman of Impulse

{T}: Add {C}.
{T}: Add {R} or {G}. This artifact deals 1 damage to you.

Forest

Bristlebane Battler

Trample, ward {2}
This creature enters with five -1/-1 counters on it.
Whenever another creature you control enters while this creature has a -1/-1 counter on it, remove a -1/-1 counter from this creature.

Temple of Malady

This land enters tapped.
When this land enters, scry 1. (Look at the top card of your library. You may put that card on the bottom.)
{T}: Add {B} or {G}.

Swamp

Consuming Fervor

Enchant creature
Enchanted creature gets +3/+3 and has "At the beginning of your upkeep, put a -1/-1 counter on this creature."

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.

Brambleback Brute

This creature enters with two -1/-1 counters on it.
{1}{R}, Remove a counter from this creature: Target creature can't block this turn. Activate only as a sorcery.

Dusk Urchins

Whenever this creature attacks or blocks, put a -1/-1 counter on it.
When this creature dies, draw a card for each -1/-1 counter on it.

Shadow Urchin

Whenever this creature attacks, blight 1. (Put a -1/-1 counter on a creature you control.)
Whenever a creature you control with one or more counters on it dies, exile that many cards from the top of your library. Until your next end step, you may play those cards.

Devoted Druid

{T}: Add {G}.
Put a -1/-1 counter on this creature: Untap this creature.

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.

Rakdos Guildgate

This land enters tapped.
{T}: Add {B} or {R}.

Dose of Dawnglow

Return target creature card from your graveyard to the battlefield. Then if it isn't your main phase, blight 2. (Put two -1/-1 counters on a creature you control.)

Grim Affliction

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.)

Temple of Malice

This land enters tapped.
When this land enters, scry 1. (Look at the top card of your library. You may put that card on the bottom.)
{T}: Add {B} or {R}.

Flourishing Defenses

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

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.)

Contagion Clasp

When this artifact enters, put a -1/-1 counter on target creature.
{4}, {T}: Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

End-Blaze Epiphany

End-Blaze Epiphany deals X damage to target creature. When that creature dies this turn, exile a number of cards from the top of your library equal to its power, then choose a card exiled this way. Until the end of your next turn, you may play that card.

Obsessive Pursuit

When this enchantment enters and at the beginning of your upkeep, you lose 1 life and create a Clue token. (It's an artifact with "{2}, Sacrifice this token: Draw a card.")
Whenever you attack, put X +1/+1 counters on target attacking creature, where X is the number of permanents you've sacrificed this turn. If X is three or more, that creature gains lifelink until end of turn.

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.

Sol Ring

Scuzzback Scrounger

At the beginning of your first main phase, you may blight 1. If you do, create a Treasure token. (To blight 1, put a -1/-1 counter on a creature you control. A Treasure token is an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Mountain

Bogslither's Embrace

As an additional cost to cast this spell, blight 1 or pay {3}. (To blight 1, put a -1/-1 counter on a creature you control.)
Exile target creature.

Talisman of Indulgence

{T}: Add {C}.
{T}: Add {B} or {R}. This artifact deals 1 damage to you.

Skinrender

When this creature enters, put three -1/-1 counters on target creature.

Golgari Rot Farm

This land enters tapped.
When this land enters, return a land you control to its owner's hand.
{T}: Add {B}{G}.

Arcane Signet

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

Liliana, Death Wielder

+2: Put a -1/-1 counter on up to one target creature.
−3: Destroy target creature with a -1/-1 counter on it.
−10: Return all creature cards from your graveyard to the battlefield.

Persist

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

Dread Tiller

When this creature enters, put a -1/-1 counter on target creature.
Whenever a creature with a -1/-1 counter on it dies, you may put a land card from your hand or graveyard onto the battlefield tapped.

Barbed Bloodletter

Flash
When this Equipment enters, attach it to target creature you control. That creature gains wither until end of turn. (It deals damage to creatures in the form of -1/-1 counters.)
Equipped creature gets +1/+2.
Equip {2}

Retched Wretch

When this creature dies, if it had a -1/-1 counter on it, return it to the battlefield under its owner's control and it loses all abilities.