Defile

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

Yahenni's Expertise

All creatures get -3/-3 until end of turn.
You may cast a spell with mana value 3 or less from your hand without paying its mana cost.

Gnarled Effigy

{4}, {T}: Put a -1/-1 counter on target creature.

Consumptive Goo

{2}{B}{B}: Target creature gets -1/-1 until end of turn. Put a +1/+1 counter on Consumptive Goo.

Dread of Night

Briarblade Adept

Whenever Briarblade Adept attacks, target creature an opponent controls gets -1/-1 until end of turn.
Encore {3}{B} ({3}{B}, Exile this card from your graveyard: For each opponent, create a token copy that attacks that opponent this turn if able. They gain haste. Sacrifice them at the beginning of the next end step. Activate only as a sorcery.)

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.

Clawing Torment

Enchant artifact or creature
As long as enchanted permanent is a creature, it gets -1/-1 and can't block.
Enchanted permanent has "At the beginning of your upkeep, you lose 1 life."

Wither and Bloom

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

Trigon of Corruption

Trigon of Corruption enters with three charge counters on it.
{B}{B}, {T}: Put a charge counter on Trigon of Corruption.
{2}, {T}, Remove a charge counter from Trigon of Corruption: Put a -1/-1 counter on target creature.

Drana, Kalastria Bloodchief

Flying
{X}{B}{B}: Target creature gets -0/-X until end of turn and Drana, Kalastria Bloodchief gets +X/+0 until end of turn.

Smog Elemental

Flying
Creatures with flying your opponents control get -1/-1.

Eye Gouge

Target creature gets -1/-1 until end of turn. If it's a Cyclops, destroy it.

Sickle Ripper

Wither (This deals damage to creatures in the form of -1/-1 counters.)

Vilis, Broker of Blood

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.)

Corrosive Mentor

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

Foul Presence

Enchant creature
Enchanted creature gets -1/-1 and has "{T}: Target creature gets -1/-1 until end of turn."

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

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.)

Ancestral Vengeance

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

Arcbound Condor

Flying
Modular 3 (This creature enters with three +1/+1 counters on it. When it dies, you may put its +1/+1 counters on target artifact creature.)
Whenever another artifact you control enters, target creature an opponent controls gets -1/-1 until end of turn.

Plague Dogs

When Plague Dogs dies, all creatures get -1/-1 until end of turn.
{2}, Sacrifice Plague Dogs: Draw a card.

Clinging Darkness

Enchant creature
Enchanted creature gets -4/-1.

Black Sun's Zenith

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

Nausea

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

Howl from Beyond

Target creature gets +X/+0 until end of turn.

Rabid Rats

{T}: Target blocking creature gets -1/-1 until end of turn.

Sadistic Obsession

Enchant creature
Enchanted creature has "{B}, {T}: Put a -1/-1 counter on target creature."

Festering Goblin

When Festering Goblin dies, target creature gets -1/-1 until end of turn.

Dead Weight

Enchant creature
Enchanted creature gets -2/-2.

Weed-Pruner Poplar

At the beginning of your upkeep, target creature other than Weed-Pruner Poplar gets -1/-1 until end of turn.

Orc Sureshot

Whenever another creature you control enters, target creature an opponent controls gets -1/-1 until end of turn.

Pestilent Haze

Choose one —
• All creatures get -2/-2 until end of turn.
• Remove two loyalty counters from each planeswalker.

Ray of Enfeeblement

Target creature gets -4/-1 until end of turn. If that creature is white, it gets -4/-4 until end of turn instead.

Looming Shade

{B}: Looming Shade gets +1/+1 until end of turn.

Pestilence

At the beginning of the end step, if no creatures are on the battlefield, sacrifice Pestilence.
{B}: Pestilence deals 1 damage to each creature and each player.

Retribution of the Ancients

{B}, Remove X +1/+1 counters from among creatures you control: Target creature gets -X/-X until end of turn.

Wretched Confluence

Choose three. You may choose the same mode more than once.
• Target player draws a card and loses 1 life.
• Target creature gets -2/-2 until end of turn.
• Return target creature card from your graveyard to your hand.

Make Obsolete

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

Festering March

Creatures your opponents control get -1/-1 until end of turn. Exile Festering March with three time counters on it.
Suspend 3—{2}{B} (Rather than cast this card from your hand, you may pay {2}{B} and exile it with three time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost.)

Kaervek, the Spiteful

Nefashu

Whenever Nefashu attacks, up to five target creatures each 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.

Twisted Experiment

Enchant creature
Enchanted creature gets +3/-1.

Battle at the Bridge

Improvise (Your artifacts can help cast this spell. Each artifact you tap after you're done activating mana abilities pays for {1}.)
Target creature gets -X/-X until end of turn. You gain X life.

Borrowed Malevolence

Escalate {2} (Pay this cost for each mode chosen beyond the first.)
Choose one or both —
• Target creature gets +1/+1 until end of turn.
• Target creature gets -1/-1 until end of turn.

Wring Flesh

Target creature gets -3/-1 until end of turn.

Yahenni, Undying Partisan

Haste
Whenever a creature an opponent controls dies, put a +1/+1 counter on Yahenni, Undying Partisan.
Sacrifice another creature: Yahenni gains indestructible until end of turn.

Nest of Scarabs

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

Shambling Ghast

When Shambling Ghast dies, choose one —
• Target creature an opponent controls gets -1/-1 until end of turn.
• Create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Savor

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

Night Clubber

When Night Clubber enters, creatures your opponents control get -1/-1 until end of turn.
Blitz {2}{B} (If you cast this spell for its blitz cost, it gains haste and "When this creature dies, draw a card." Sacrifice it at the beginning of the next end step.)

Moment of Craving

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

Fourth Bridge Prowler

When Fourth Bridge Prowler enters, you may have target creature get -1/-1 until end of turn.

Dark Ritual

Tooth Collector

When Tooth Collector enters, target creature an opponent controls gets -1/-1 until end of turn.
Delirium — At the beginning of each opponent's upkeep, if there are four or more card types among cards in your graveyard, target creature that player controls gets -1/-1 until end of turn.

Nightmare's Thirst

You gain 1 life. Target creature gets -X/-X until end of turn, where X is the amount of life you gained this turn.

Umezawa's Jitte

Whenever equipped creature deals combat damage, put two charge counters on Umezawa's Jitte.
Remove a charge counter from Umezawa's Jitte: Choose one —
• Equipped creature gets +2/+2 until end of turn.
• Target creature gets -1/-1 until end of turn.
• You gain 2 life.
Equip {2}

Shrivel

Terisiare's Devastation

You lose X life and create X tapped Powerstone tokens. Then all creatures get -1/-1 until end of turn for each artifact you control. (The tokens are artifacts with "{T}: Add {C}. This mana can't be spent to cast a nonartifact spell.")

Demon of Dark Schemes

Flying
When Demon of Dark Schemes enters, all other creatures get -2/-2 until end of turn.
Whenever another creature dies, you get {E} (an energy counter).
{2}{B}, Pay {E}{E}{E}{E}: Put target creature card from a graveyard onto the battlefield under your control tapped.

Death's-Head Buzzard

Flying
When Death's-Head Buzzard dies, all creatures get -1/-1 until end of turn.

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.)

Painbringer

{T}, Exile any number of cards from your graveyard: Target creature gets -X/-X until end of turn, where X is the number of cards exiled this way.

Ruthless Sniper

Whenever you cycle or discard a card, you may pay {1}. If you do, put a -1/-1 counter on target creature.

Scent of Nightshade

Reveal any number of black cards in your hand. Target creature gets -X/-X until end of turn, where X is the number of cards revealed this way.

Krovikan Plague

Enchant non-Wall creature you control
When Krovikan Plague enters, draw a card at the beginning of the next turn's upkeep.
Tap enchanted creature: Krovikan Plague deals 1 damage to any target. Put a -0/-1 counter on enchanted creature. Activate only if enchanted creature is untapped.

Disease Carriers

When Disease Carriers dies, target creature gets -2/-2 until end of turn.

Plague Engineer

Deathtouch
As Plague Engineer enters, choose a creature type.
Creatures of the chosen type your opponents control get -1/-1.

Dreamspoiler Witches

Flying
Whenever you cast a spell during an opponent's turn, you may have target creature get -1/-1 until end of turn.

Lose Hope

Target creature gets -1/-1 until end of turn. Scry 2. (Look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Curse of Death's Hold

Enchant player
Creatures enchanted player controls get -1/-1.

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.

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.

Crown of Suspicion

Enchant creature
Enchanted creature gets +2/-1.
Sacrifice Crown of Suspicion: Enchanted creature and other creatures that share a creature type with it get +2/-1 until end of turn.

Enfeeblement

Enchant creature (Target a creature as you cast this. This card enters attached to that creature.)
Enchanted creature gets -2/-2.

Festering Mummy

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

Withering Wisps

At the beginning of the end step, if no creatures are on the battlefield, sacrifice Withering Wisps.
{B}: Withering Wisps deals 1 damage to each creature and each player. Activate no more times each turn than the number of snow Swamps you control.

Cabal Torturer

{B}, {T}: Target creature gets -1/-1 until end of turn.
Threshold — {3}{B}{B}, {T}: Target creature gets -2/-2 until end of turn. Activate only if seven or more cards are in your graveyard.

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.)

Demonic Stench

Each creature that blocked this turn gets -1/-1 until end of turn. (Then exile this card. You may cast the creature later from exile.)

Hezrou

Whenever one or more creatures you control become blocked, each blocking creature gets -1/-1 until end of turn.

Hezrou // Demonic Stench

Nowhere to Run

Flash
When Nowhere to Run enters, target creature an opponent controls gets -3/-3 until end of turn.
Creatures your opponents control can be the targets of spells and abilities as though they didn't have hexproof. Ward abilities of those creatures don't trigger.

Festering Newt

When Festering Newt dies, target creature an opponent controls gets -1/-1 until end of turn. That creature gets -4/-4 instead if you control a creature named Bogbrew Witch.

Midnight Banshee

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.

Caustic Crawler

Landfall — Whenever a land you control enters, you may have target creature get -1/-1 until end of turn.

Serrated Arrows

Serrated Arrows enters with three arrowhead counters on it.
At the beginning of your upkeep, if there are no arrowhead counters on Serrated Arrows, sacrifice it.
{T}, Remove an arrowhead counter from Serrated Arrows: Put a -1/-1 counter on target creature.

Crippling Blight

Enchant creature
Enchanted creature gets -1/-1 and can't block.

Despondency

Enchant creature
Enchanted creature gets -2/-0.
When Despondency is put into a graveyard from the battlefield, return Despondency to its owner's hand.

Liliana's Influence

Put a -1/-1 counter on each creature you don't control. You may search your library and/or graveyard for a card named Liliana, Death Wielder, reveal it, and put it into your hand. If you search your library this way, shuffle.

Cinderbones

Wither (This deals damage to creatures in the form of -1/-1 counters.)
{1}{B}: Regenerate Cinderbones.

Massacre Wurm

When this creature enters, creatures your opponents control get -2/-2 until end of turn.
Whenever a creature an opponent controls dies, that player loses 2 life.

Engineered Plague

As Engineered Plague enters, choose a creature type.
All creatures of the chosen type get -1/-1.

Fungal Infection

Target creature gets -1/-1 until end of turn. Create a 1/1 green Saproling creature token.

Erebos's Intervention

Choose one —
• Target creature gets -X/-X until end of turn. You gain X life.
• Exile up to twice X target cards from graveyards.

Ascendant Evincar

Flying (This creature can't be blocked except by creatures with flying or reach.)
Other black creatures get +1/+1.
Nonblack creatures get -1/-1.

Doomwake Giant

Constellation — Whenever Doomwake Giant or another enchantment you control enters, creatures your opponents control get -1/-1 until end of turn.

Maha, Its Feathers Night

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

Profane Command

Choose two —
• Target player loses X life.
• Return target creature card with mana value X or less from your graveyard to the battlefield.
• Target creature gets -X/-X until end of turn.
• Up to X target creatures gain fear until end of turn. (They can't be blocked except by artifact creatures and/or black creatures.)

Soul Snuffers

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