Dead Revels

Spectacle {1}{B} (You may cast this spell for its spectacle cost rather than its mana cost if an opponent lost life this turn.)
Return up to two target creature cards from your graveyard to your hand.

Fourth Bridge Prowler

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

Defile

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

Tower of Coireall

{T}: Target creature can't be blocked by Walls this turn.

Scale of Chiss-Goria

Flash
Affinity for artifacts (This spell costs {1} less to cast for each artifact you control.)
{T}: Target creature gets +0/+1 until end of turn.

Rathi Trapper

Flensermite

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
Lifelink (Damage dealt by this creature also causes you to gain that much life.)

Horobi, Death's Wail

Flying
Whenever a creature becomes the target of a spell or ability, destroy that creature.

Death's Duet

Return two target creature cards from your graveyard to your hand.

Deathspore Thallid

At the beginning of your upkeep, put a spore counter on Deathspore Thallid.
Remove three spore counters from Deathspore Thallid: Create a 1/1 green Saproling creature token.
Sacrifice a Saproling: Target creature gets -1/-1 until end of turn.

Gravebind

Target creature can't be regenerated this turn.
Draw a card at the beginning of the next turn's upkeep.

Death Watch

Enchant creature
When enchanted creature dies, its controller loses life equal to its power and you gain life equal to its toughness.

Toxic Nim

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
{B}: Regenerate Toxic Nim.

Alley Grifters

Whenever Alley Grifters becomes blocked, defending player discards a card.

Dauthi Trapper

{T}: Target creature gains shadow until end of turn. (It can block or be blocked by only creatures with shadow.)

Dauthi Jackal

Shadow (This creature can block or be blocked by only creatures with shadow.)
{B}{B}, Sacrifice Dauthi Jackal: Destroy target blocking creature.

Disturbing Plot

Return target creature card from a graveyard to its owner's hand.
Conspire (As you cast this spell, you may tap two untapped creatures you control that share a color with it. When you do, copy it and you may choose a new target for the copy.)

Disfigure

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

Gray Merchant of Asphodel

When Gray Merchant of Asphodel enters, each opponent loses X life, where X is your devotion to black. You gain life equal to the life lost this way. (Each {B} in the mana costs of permanents you control counts toward your devotion to black.)

Dauthi Marauder

Shadow (This creature can block or be blocked by only creatures with shadow.)

Bladebrand

Target creature gains deathtouch until end of turn.
Draw a card.

Drifting Shade

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

Nighthaze

Target creature gains swampwalk until end of turn. (It can't be blocked as long as defending player controls a Swamp.)
Draw a card.

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.)

Forever Young

Put any number of target creature cards from your graveyard on top of your library.
Draw a card.

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.

Bog Smugglers

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)

Ancestral Vengeance

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

Cannibalize

Choose two target creatures controlled by the same player. Exile one of those creatures and put two +1/+1 counters on the other.

Blessing of Belzenlok

Target creature gets +2/+1 until end of turn. If it's legendary, it also gains lifelink until end of turn.

Squee's Toy

{T}: Prevent the next 1 damage that would be dealt to target creature this turn.

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.

Contagious Nim

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

Consume Spirit

Spend only black mana on X.
Consume Spirit deals X damage to any target and you gain X life.

Disciple of Tevesh Szat

{T}: Target creature gets -1/-1 until end of turn.
{4}{B}{B}, {T}, Sacrifice Disciple of Tevesh Szat: Target creature gets -6/-6 until end of turn.

Dark Ritual

Frozen Shade

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

Phyresis

Enchant creature
Enchanted creature has infect. (It deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

Dauthi Mercenary

Shadow (This creature can block or be blocked by only creatures with shadow.)
{1}{B}: Dauthi Mercenary gets +1/+0 until end of turn.

Dauthi Slayer

Shadow (This creature can block or be blocked by only creatures with shadow.)
Dauthi Slayer attacks each combat if able.

Blister Beetle

When Blister Beetle enters, target creature gets -1/-1 until end of turn.

Dirge of Dread

All creatures gain fear until end of turn. (They can't be blocked except by artifact creatures and/or black creatures.)
Cycling {1}{B} ({1}{B}, Discard this card: Draw a card.)
When you cycle Dirge of Dread, you may have target creature gain fear until end of turn.

Dirtwater Wraith

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)
{B}: Dirtwater Wraith gets +1/+0 until end of turn.

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice Mind Stone: Draw a card.

Blood Glutton

Lifelink (Damage dealt by this creature also causes you to gain that much life.)

Helm of Chatzuk

{1}, {T}: Target creature gains banding until end of turn. (Any creatures with banding, and up to one without, can attack in a band. Bands are blocked as a group. If any creatures with banding a player controls are blocking or being blocked by a creature, that player divides that creature's combat damage, not its controller, among any of the creatures it's being blocked by or is blocking.)

Shadow Alley Denizen

Whenever another black creature you control enters, target creature gains intimidate until end of turn. (It can't be blocked except by artifact creatures and/or creatures that share a color with it.)

Death Denied

Return X target creature cards from your graveyard to your hand.

Aphotic Wisps

Target creature becomes black and gains fear until end of turn. (It can't be blocked except by artifact creatures and/or black creatures.)
Draw a card.

Footbottom Feast

Dungeon Shade

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

Afflict

Target creature gets -1/-1 until end of turn.
Draw a card.

Agent of Shauku

{1}{B}, Sacrifice a land: Target creature gets +2/+0 until end of turn.

Eye Gouge

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

Fungal Infection

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

Festering Mummy

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

Blackcleave Goblin

Haste
Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

Arcane Signet

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

Xenic Poltergeist

{T}: Until your next upkeep, target noncreature artifact becomes an artifact creature with power and toughness each equal to its mana value.

Tooth of Chiss-Goria

Flash
Affinity for artifacts (This spell costs {1} less to cast for each artifact you control.)
{T}: Target creature gets +1/+0 until end of turn.

Sorceress Queen

{T}: Target creature other than Sorceress Queen has base power and toughness 0/2 until end of turn.

Ghosts of the Damned

{T}: Target creature gets -1/-0 until end of turn.

Swamp

Dauthi Horror

Shadow (This creature can block or be blocked by only creatures with shadow.)
Dauthi Horror can't be blocked by white creatures.

Armor Thrull

{T}, Sacrifice Armor Thrull: Put a +1/+2 counter on target creature.

Dauthi Embrace

{B}{B}: Target creature gains shadow until end of turn. (It can block or be blocked by only creatures with shadow.)