Overkill

Target creature gets -0/-9999 until end of turn.

Dismember

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

Primaris Eliminator

When this creature enters, choose one —
• Executioner Round — Destroy target creature.
• Hyperfrag Round — Creatures target player controls get -2/-2 until end of turn.

Mephitic Vapors

All creatures get -1/-1 until end of turn.
Surveil 2. (Look at the top two cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)

Infest

All creatures get -2/-2 until end of turn.

Skulduggery

Until end of turn, target creature you control gets +1/+1 and target creature an opponent controls gets -1/-1.

Sultai Runemark

Enchant creature
Enchanted creature gets +2/+2.
Enchanted creature has deathtouch as long as you control a green or blue permanent. (Any amount of damage it deals to a creature is enough to destroy it.)

Defile

Target creature gets -1/-1 until end of turn for each Swamp you control.

Homicidal Seclusion

As long as you control exactly one creature, that creature gets +3/+1 and has lifelink.

Dark Favor

Enchant creature
When this Aura enters, you lose 1 life.
Enchanted creature gets +3/+1.

The Black Breath

Creatures your opponents control get -1/-1 until end of turn. The Ring tempts you.

Ancestral Vengeance

Enchant creature
When this Aura enters, put a +1/+1 counter on target creature you control.
Enchanted creature gets -1/-1.

Cloudkill

All creatures get -X/-X until end of turn, where X is the greatest mana value of a commander you own on the battlefield or in the command zone.

Disfigure

Target creature gets -2/-2 until end of turn.

Blackblade Reforged

Equipped creature gets +1/+1 for each land you control.
Equip legendary creature {3}
Equip {7}

Ob Nixilis's Cruelty

Target creature gets -5/-5 until end of turn. If that creature would die this turn, exile it instead.

Decree of Pain

Destroy all creatures. They can't be regenerated. Draw a card for each creature destroyed this way.
Cycling {3}{B}{B} ({3}{B}{B}, Discard this card: Draw a card.)
When you cycle this card, all creatures get -2/-2 until end of turn.

Bleed Dry

Target creature gets -13/-13 until end of turn. If that creature would die this turn, exile it instead.

Gruesome Realization

Choose one —
• You draw two cards and you lose 2 life.
• Creatures your opponents control get -1/-1 until end of turn.

Wither and Bloom

Target creature gets -3/-3 until end of turn.
{1}{B}, Exile this card from your graveyard: Put a +1/+1 counter on target creature you control. Activate only as a sorcery.

Tragic Slip

Target creature gets -1/-1 until end of turn.
Morbid — That creature gets -13/-13 until end of turn instead if a creature died this turn.

Nameless Inversion

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

Stab Wound

Enchant creature
Enchanted creature gets -2/-2.
At the beginning of the upkeep of enchanted creature's controller, that player loses 2 life.

Dark Ritual

Reanimate

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

Maha, Its Feathers Night

Flying, trample
Ward—Discard a card.
Creatures your opponents control have base toughness 1.

Cower in Fear

Creatures your opponents control get -1/-1 until end of turn.

Make Obsolete

Kaervek, the Spiteful

Dead Weight

Enchant creature
Enchanted creature gets -2/-2.

Swamp

Ashnod's Intervention

Until end of turn, target creature gets +2/+0 and gains "When this creature dies or is put into exile from the battlefield, return it to its owner's hand."

Ordeal of Erebos

Enchant creature
Whenever enchanted creature attacks, put a +1/+1 counter on it. Then if it has three or more +1/+1 counters on it, sacrifice this Aura.
When you sacrifice this Aura, target player discards two cards.

Death's Approach

Enchant creature
Enchanted creature gets -X/-X, where X is the number of creature cards in its controller's graveyard.

Night of Souls' Betrayal

Vow of Malice

Enchant creature
Enchanted creature gets +2/+2, has intimidate, and can't attack you or planeswalkers you control. (A creature with intimidate can't be blocked except by artifact creatures and/or creatures that share a color with it.)

Toxic Deluge

As an additional cost to cast this spell, pay X life.
All creatures get -X/-X until end of turn.

Blight Grenade

Destroy target creature.
All creatures get -3/-3 until end of turn.

Faerie Fencing

Target creature gets -X/-X until end of turn. That creature gets an additional -3/-3 until end of turn if you controlled a Faerie as you cast this spell.

Nausea

All creatures get -1/-1 until end of turn.

Evil Reawakened

Return target creature card from your graveyard to the battlefield with two additional +1/+1 counters on it.

Quag Sickness

Enchant creature
Enchanted creature gets -1/-1 for each Swamp you control.

Drown in Sorrow

All creatures get -2/-2 until end of turn. Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Vicious Offering

Kicker—Sacrifice a creature. (You may sacrifice a creature in addition to any other costs as you cast this spell.)
Target creature gets -2/-2 until end of turn. If this spell was kicked, that creature gets -5/-5 until end of turn instead.

Mark of the Vampire

Enchant creature
Enchanted creature gets +2/+2 and has lifelink.

Predator's Gambit

Enchant creature
Enchanted creature gets +2/+1.
Enchanted creature has intimidate as long as its controller controls no other creatures. (It can't be blocked except by artifact creatures and/or creatures that share a color with it.)

Drown in Ichor

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.)

Feast of Succession

All creatures get -4/-4 until end of turn. You become the monarch.

Flatten

Target creature gets -4/-4 until end of turn.

Neutralize the Guards

Creatures target opponent controls get -1/-1 until end of turn. Surveil 2. (Look at the top two cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)

Golden Demise

Ascend (If you control ten or more permanents, you get the city's blessing for the rest of the game.)
All creatures get -2/-2 until end of turn. If you have the city's blessing, instead only creatures your opponents control get -2/-2 until end of turn.

Nightmarish End

Target creature gets -X/-X until end of turn, where X is the number of cards in your hand.

Crippling Fatigue

Target creature gets -2/-2 until end of turn.
Flashback—{1}{B}, Pay 3 life. (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Massacre Girl

Menace
When Massacre Girl enters, each other creature gets -1/-1 until end of turn. Whenever a creature dies this turn, each creature other than Massacre Girl gets -1/-1 until end of turn.

Festergloom

Nonblack creatures get -1/-1 until end of turn.

Glistening Deluge

All creatures get -1/-1 until end of turn. Creatures that are green and/or white get an additional -2/-2 until end of turn.

Ichor Slick

Target creature gets -3/-3 until end of turn.
Cycling {2} ({2}, Discard this card: Draw a card.)
Madness {3}{B} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)

Tragic Fall

Target creature gets -3/-3 until end of turn.
Hellbent — That creature gets -13/-13 until end of turn instead if you have no cards in hand.

Eyeblight Massacre

Non-Elf creatures get -2/-2 until end of turn.

Vayne's Treachery

Kicker—Sacrifice an artifact or creature. (You may sacrifice an artifact or creature in addition to any other costs as you cast this spell.)
Target creature gets -2/-2 until end of turn. If this spell was kicked, that creature gets -6/-6 until end of turn instead.

Vow of Torment

Enchant creature
Enchanted creature gets +2/+2, has menace, and can't attack you or planeswalkers you control. (It can't be blocked except by two or more creatures.)

Final Flourish

Shelob's Ambush

Target creature gets +1/+2 and gains deathtouch until end of turn. Create a Food token. (It's an artifact with "{2}, {T}, Sacrifice this token: You gain 3 life.")

Locthwain Scorn

Target creature gets -3/-3 until end of turn. You gain 2 life.

Virtue of Persistence

At the beginning of your upkeep, put target creature card from a graveyard onto the battlefield under your control.

Virtue of Persistence // Locthwain Scorn

Nuclear Fallout

Each creature gets twice -X/-X until end of turn. Each player gets X rad counters.

Poison the Waters

Choose one —
• All creatures get -1/-1 until end of turn.
• Target player reveals their hand. You choose an artifact or creature card from it. That player discards that card.

Languish

All creatures get -4/-4 until end of turn.

Champion's Helm

Equipped creature gets +2/+2.
As long as equipped creature is legendary, it has hexproof. (It can't be the target of spells or abilities your opponents control.)
Equip {1}

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.

Cartouche of Ambition

Enchant creature you control
When this Aura enters, you may put a -1/-1 counter on target creature.
Enchanted creature gets +1/+1 and has lifelink.