Thraximundar

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

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.

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.

Equilibrium

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

Evil Twin

You may have Evil Twin enter 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."

Crypt Lurker

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

Floodgate

Defender
When Floodgate has flying, sacrifice it.
When Floodgate leaves the battlefield, it deals damage to each nonblue creature without flying equal to half the number of Islands you control, rounded down.

Curiosity

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

Booby Trap

As Booby Trap enters, 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.

Island

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.

No Mercy

Whenever a creature deals damage to you, destroy it.

Plague Dogs

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

Dreamcatcher

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

Clone

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

Screams from Within

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

Rod of Ruin

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

Swamp

Carnival of Souls

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

Mad Dog

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

Hecatomb

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

Sentinel

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

Slum Reaper

When Slum Reaper enters, each player sacrifices a creature of their choice.

Death Watch

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

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.

Lost Legion

When Lost Legion enters, 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.)

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.

Mistwalker

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

Blood Mist

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

Darkest Hour

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.

Tormented Soul

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

Devouring Swarm

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

Dark Revenant

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

Fallen Angel

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

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.

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.

Body Snatcher

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

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.)

Oculus

Anger

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

Mountain

Murder of Crows

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

Zombify

Return target creature card from your graveyard to the battlefield.

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.