Plague Dogs

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

Runesword

{3}, {T}: Target attacking creature gets +2/+0 until end of turn. When that creature leaves the battlefield this turn, sacrifice Runesword. If the creature deals damage to a creature this turn, the creature dealt damage can't be regenerated this turn. If a creature dealt damage by the targeted creature would die this turn, exile that creature instead.

Mad Dog

At the beginning of your end step, if Mad Dog didn't attack or come under your control this turn, sacrifice it.

Thraximundar

Haste
Whenever Thraximundar attacks, defending player sacrifices a creature.
Whenever a player sacrifices a creature, you may put a +1/+1 counter on Thraximundar.

Equilibrium

Whenever you cast a creature spell, you may pay {1}. If you do, return target creature to its owner's hand.

Booby Trap

As Booby Trap enters the battlefield, choose an opponent and a card name other than a basic land card name.
The chosen player reveals each card they draw.
When the chosen player draws a card with the chosen name, sacrifice Booby Trap. If you do, Booby Trap deals 10 damage to that player.

Endling

{B}: Endling gains menace until end of turn.
{B}: Endling gains deathtouch until end of turn.
{B}: Endling gains undying until end of turn. (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.)
{1}: Endling gets +1/-1 or -1/+1 until end of turn.

Dark Revenant

Flying
When Dark Revenant dies, put it on top of its owner's library.

Devouring Swarm

Flying
Sacrifice a creature: Devouring Swarm gets +1/+1 until end of turn.

Mistwalker

Changeling (This card is every creature type.)
Flying
{1}{U}: Mistwalker gets +1/-1 until end of turn.

Gallowbraid

Trample
Cumulative upkeep—Pay 1 life. (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)

Tortured Existence

{B}, Discard a creature card: Return target creature card from your graveyard to your hand.

Island

Hecatomb

When Hecatomb enters the battlefield, sacrifice Hecatomb unless you sacrifice four creatures.
Tap an untapped Swamp you control: Hecatomb deals 1 damage to any target.

Extruder

Echo {4} (At the beginning of your upkeep, if this came under your control since the beginning of your last upkeep, sacrifice it unless you pay its echo cost.)
Sacrifice an artifact: Put a +1/+1 counter on target creature.

Carnival of Souls

Whenever a creature enters the battlefield, you lose 1 life and add {B}.

Evil Twin

You may have Evil Twin enter the battlefield as a copy of any creature on the battlefield, except it has "{U}{B}, {T}: Destroy target creature with the same name as this creature."

Kill Switch

{2}, {T}: Tap all other artifacts. They don't untap during their controllers' untap steps for as long as Kill Switch remains tapped.

Mountain

Ichorid

Haste
At the beginning of the end step, sacrifice Ichorid.
At the beginning of your upkeep, if Ichorid is in your graveyard, you may exile a black creature card other than Ichorid from your graveyard. If you do, return Ichorid to the battlefield.

Rod of Ruin

{3}, {T}: Rod of Ruin deals 1 damage to any target.

Dreamcatcher

Whenever you cast a Spirit or Arcane spell, you may sacrifice Dreamcatcher. If you do, draw a card.

Murder of Crows

Flying
Whenever another creature dies, you may draw a card. If you do, discard a card.

Filth

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)
As long as Filth is in your graveyard and you control a Swamp, creatures you control have swampwalk.

Curiosity

Enchant creature
Whenever enchanted creature deals damage to an opponent, you may draw a card.

Clone

You may have Clone enter the battlefield as a copy of any creature on the battlefield.

Necrite

Whenever Necrite attacks and isn't blocked, you may sacrifice it. If you do, destroy target creature defending player controls. It can't be regenerated.

Tormented Soul

Tormented Soul can't block and can't be blocked.

Eternal Thirst

Enchant creature
Enchanted creature has lifelink and "Whenever a creature an opponent controls dies, put a +1/+1 counter on this creature." (Damage dealt by a creature with lifelink also causes its controller to gain that much life.)

Anger

Haste
As long as Anger is in your graveyard and you control a Mountain, creatures you control have haste.

Body Snatcher

When Body Snatcher enters the battlefield, exile it unless you discard a creature card.
When Body Snatcher dies, exile Body Snatcher and return target creature card from your graveyard to the battlefield.

Lost Legion

When Lost Legion enters the battlefield, scry 2. (Look at the top two cards of your library, then put any number of them on the bottom of your library and the rest on top in any order.)

Oculus

Zombify

Return target creature card from your graveyard to the battlefield.

Slum Reaper

When Slum Reaper enters the battlefield, each player sacrifices a creature.

Sentinel

{0}: Change Sentinel's base toughness to 1 plus the power of target creature blocking or blocked by Sentinel. (This effect lasts indefinitely.)

Death Watch

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

Crypt Lurker

When Crypt Lurker enters the battlefield, you may sacrifice a creature or discard a creature card. If you do, draw a card.

No Mercy

Whenever a creature deals damage to you, destroy it.

Fallen Angel

Flying
Sacrifice a creature: Fallen Angel gets +2/+1 until end of turn.

Screams from Within

Enchant creature
Enchanted creature gets -1/-1.
When enchanted creature dies, return Screams from Within from your graveyard to the battlefield.

Iron Maiden

At the beginning of each opponent's upkeep, Iron Maiden deals X damage to that player, where X is the number of cards in their hand minus 4.

Floodgate

Defender (This creature can't attack.)
When Floodgate has flying, sacrifice it.
When Floodgate leaves the battlefield, it deals damage equal to half the number of Islands you control, rounded down, to each nonblue creature without flying.

Blood Mist

At the beginning of combat on your turn, target creature you control gains double strike until end of turn.