Etrata, the Silencer

Etrata can't be blocked.
Whenever Etrata deals combat damage to a player, exile target creature that player controls and put a hit counter on that card. That player loses the game if they own three or more exiled cards with hit counters on them. Etrata's owner shuffles Etrata into their library.

Reliquary Tower

You have no maximum hand size.
{T}: Add {C}.

Callidus Assassin

Flash
Polymorphine — You may have this creature enter tapped as a copy of any creature on the battlefield, except it has "When this creature enters, destroy up to one other target creature with the same name as this creature."

Scry 1. (Look at the top card of your library. You may put that card on the bottom.)
Draw a card.

Brainstorm

Draw three cards, then put two cards from your hand on top of your library in any order.

Prismatic Vista

{T}, Pay 1 life, Sacrifice this land: Search your library for a basic land card, put it onto the battlefield, then shuffle.

Eyeblight Assassin

When this creature enters, target creature an opponent controls gets -1/-1 until end of turn.

Blade of Selves

Equipped creature has myriad. (Whenever it attacks, for each opponent other than defending player, you may create a token copy that's tapped and attacking that player or a planeswalker they control. Exile the tokens at end of combat.)
Equip {4}

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.

Thought Vessel

Midnight Assassin

Flying
Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)

Guildsworn Prowler

Deathtouch
When this creature dies, if it wasn't blocking, draw a card.

Negate

Baleful Strix

Flying, deathtouch
When this creature enters, draw a card.

Arcane Signet

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

Orzhov Euthanist

Haunt (When this creature dies, exile it haunting target creature.)
When this creature enters or the creature it haunts dies, destroy target creature that was dealt damage this turn.

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.

Morbid Opportunist

Whenever one or more other creatures die, draw a card. This ability triggers only once each turn.

Underground Sea

Shipwreck Marsh

This land enters tapped unless you control two or more other lands.
{T}: Add {U} or {B}.

Shadow Rift

Target creature gains shadow until end of turn. (It can block or be blocked by only creatures with shadow.)
Draw a card.

Sign in Blood

Target player draws two cards and loses 2 life.

Cut Down

Destroy target creature with total power and toughness 5 or less.

Sunken Hollow

({T}: Add {U} or {B}.)
This land enters tapped unless you control two or more basic lands.

Diabolic Tutor

Search your library for a card, put that card into your hand, then shuffle.

Nekrataal

First strike
When this creature enters, destroy target nonartifact, nonblack creature. That creature can't be regenerated.

Termination Facilitator

{T}: Put a bounty counter on target creature or planeswalker. Activate only as a sorcery.
Whenever a creature or planeswalker an opponent controls with a bounty counter on it is dealt damage, destroy it.

Murder

An Offer You Can't Refuse

Counter target noncreature spell. Its controller creates two Treasure tokens. (They're artifacts with "{T}, Sacrifice this token: Add one mana of any color.")

Island

Command Tower

Kindred Dominance

Choose a creature type. Destroy all creatures that aren't of the chosen type.

Fierce Guardianship

If you control a commander, you may cast this spell without paying its mana cost.
Counter target noncreature spell.

Kiku's Shadow

Target creature deals damage to itself equal to its power.

Hooded Assassin

When this creature enters, choose one —
• Put a +1/+1 counter on this creature.
• Destroy target creature that was dealt damage this turn.

Preordain

Scry 2, then draw a card. (To 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.)

Sunken Ruins

{T}: Add {C}.
{U/B}, {T}: Add {U}{U}, {U}{B}, or {B}{B}.

Feed the Swarm

Destroy target creature or enchantment an opponent controls. You lose life equal to that permanent's mana value.

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice this artifact: Draw a card.

Counterspell

Drowned Catacomb

This land enters tapped unless you control an Island or a Swamp.
{T}: Add {U} or {B}.

Scarblade Elite

{T}, Exile an Assassin card from your graveyard: Destroy target creature.

Rapid Hybridization

Destroy target creature. It can't be regenerated. That creature's controller creates a 3/3 green Frog Lizard creature token.

Ravenloft Adventurer

When this creature enters, you take the initiative.
If a creature an opponent controls would die, instead exile it and put a hit counter on it.
Whenever this creature attacks, if you've completed a dungeon, defending player loses 1 life for each card they own in exile with a hit counter on it.

Mari, the Killing Quill

Whenever a creature an opponent controls dies, exile it with a hit counter on it.
Assassins, Mercenaries, and Rogues you control have deathtouch and "Whenever this creature deals combat damage to a player, you may remove a hit counter from a card that player owns in exile. If you do, draw a card and create two Treasure tokens."

Dark Ritual

Countersquall

Counter target noncreature spell. Its controller loses 2 life.

Dimir Signet

Wayfarer's Bauble

{2}, {T}, Sacrifice this artifact: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Aetherize

Return all attacking creatures to their owner's hand.

Ponder

Look at the top three cards of your library, then put them back in any order. You may shuffle.
Draw a card.

Watery Grave

({T}: Add {U} or {B}.)
As this land enters, you may pay 2 life. If you don't, it enters tapped.

Vampiric Tutor

Search your library for a card, then shuffle and put that card on top. You lose 2 life.

Pongify

Destroy target creature. It can't be regenerated. Its controller creates a 3/3 green Ape creature token.

Hero's Downfall

Slip Out the Back

Put a +1/+1 counter on target creature. It phases out. (Treat it and anything attached to it as though they don't exist until its controller's next turn.)

Go for the Throat

Guul Draz Assassin

Level up {1}{B} ({1}{B}: Put a level counter on this. Level up only as a sorcery.)
LEVEL 2-3
2/2
{B}, {T}: Target creature gets -2/-2 until end of turn.
LEVEL 4+
4/4
{B}, {T}: Target creature gets -4/-4 until end of turn.

Morphic Pool

This land enters tapped unless you have two or more opponents.
{T}: Add {U} or {B}.

Aven Heartstabber

Flying
As long as there are five or more mana values among cards in your graveyard, this creature gets +2/+2 and has deathtouch.
When this creature dies, mill two cards, then draw a card.

Swamp

Doom Blade

River of Tears

{T}: Add {U}. If you played a land this turn, add {B} instead.

Arcane Denial

Counter target spell. Its controller may draw up to two cards at the beginning of the next turn's upkeep.
You draw a card at the beginning of the next turn's upkeep.

Royal Assassin

Mystical Tutor

Search your library for an instant or sorcery card, reveal it, then shuffle and put that card on top.

In Garruk's Wake

Destroy all creatures you don't control and all planeswalkers you don't control.

Agent of the Fates

Deathtouch
Heroic — Whenever you cast a spell that targets this creature, each opponent sacrifices a creature of their choice.

Gixian Skullflayer

At the beginning of your upkeep, if there are three or more creature cards in your graveyard, put a +1/+1 counter on this creature.

Assassinate

Changeling Outcast

Changeling (This card is every creature type.)
This creature can't block and can't be blocked.

Damnation

Destroy all creatures. They can't be regenerated.

Infernal Grasp

Destroy target creature. You lose 2 life.

Night's Whisper

Murkwater Pathway

Clearwater Pathway

Clearwater Pathway // Murkwater Pathway

Vraska's Finisher

When this creature enters, destroy target creature or planeswalker an opponent controls that was dealt damage this turn.

Dismember

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

Polluted Delta

{T}, Pay 1 life, Sacrifice this land: Search your library for an Island or Swamp card, put it onto the battlefield, then shuffle.