Thrill-Kill Assassin

Deathtouch
Unleash (You may have this creature enter the battlefield with a +1/+1 counter on it. It can't block as long as it has a +1/+1 counter on it.)

Dark Impostor

{4}{B}{B}: Exile target creature and put a +1/+1 counter on Dark Impostor.
Dark Impostor has all activated abilities of all creature cards exiled with it.

Stronghold Assassin

{T}, Sacrifice a creature: Destroy target nonblack creature.

Sakashima the Impostor

You may have Sakashima the Impostor enter the battlefield as a copy of any creature on the battlefield, except its name is Sakashima the Impostor, it's legendary in addition to its other types, and it has "{2}{U}{U}: Return this creature to its owner's hand at the beginning of the next end step."

Aqueous Form

Enchant creature
Enchanted creature can't be blocked.
Whenever enchanted creature attacks, scry 1. (Look at the top card of your library. You may put that card on the bottom of your library.)

Sheoldred, Whispering One

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)
At the beginning of your upkeep, return target creature card from your graveyard to the battlefield.
At the beginning of each opponent's upkeep, that player sacrifices a creature.

Vein Ripper

Flying
Ward—Sacrifice a creature.
Whenever a creature dies, target opponent loses 2 life and you gain 2 life.

Island

Arcane Signet

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

Virtus the Veiled

Partner with Gorm the Great (When this creature enters the battlefield, target player may put Gorm into their hand from their library, then shuffle.)
Deathtouch
Whenever Virtus the Veiled deals combat damage to a player, that player loses half their life, rounded up.

Fellwar Stone

{T}: Add one mana of any color that a land an opponent controls could produce.

Bribery

Search target opponent's library for a creature card and put that card onto the battlefield under your control. Then that player shuffles.

Hired Poisoner

Negate

Sol Ring

Swamp

Dimir Aqueduct

Dimir Aqueduct enters the battlefield tapped.
When Dimir Aqueduct enters the battlefield, return a land you control to its owner's hand.
{T}: Add {U}{B}.

Helm of the Host

At the beginning of combat on your turn, create a token that's a copy of equipped creature, except the token isn't legendary. That token gains haste.
Equip {5}

Phyrexian Arena

At the beginning of your upkeep, you draw a card and you lose 1 life.

Grim Tutor

Search your library for a card, put that card into your hand, then shuffle. You lose 3 life.

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.

Dimir Signet

Arcane Lighthouse

{T}: Add {C}.
{1}, {T}: Until end of turn, creatures your opponents control lose hexproof and shroud and can't have hexproof or shroud.

Ramses, Assassin Lord

Deathtouch
Other Assassins you control get +1/+1.
Whenever a player loses the game, if they were attacked this turn by an Assassin you controlled, you win the game.

Rogue's Passage

{T}: Add {C}.
{4}, {T}: Target creature can't be blocked this turn.

Archetype of Imagination

Creatures you control have flying.
Creatures your opponents control lose flying and can't have or gain flying.

Counterspell

Trailblazer's Boots

Equipped creature has nonbasic landwalk. (It can't be blocked as long as defending player controls a nonbasic land.)
Equip {2}

Big Game Hunter

When Big Game Hunter enters the battlefield, destroy target creature with power 4 or greater. It can't be regenerated.
Madness {B} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)

Jester's Cap

{2}, {T}, Sacrifice Jester's Cap: Search target player's library for three cards and exile them. Then that player shuffles.

Morphic Pool

Morphic Pool enters the battlefield tapped unless you have two or more opponents.
{T}: Add {U} or {B}.

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."

Kindred Dominance

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

Lightning Greaves

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.)
Equip {0}

Etrata, the Silencer

Etrata, the Silencer 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.

Guildsworn Prowler

Deathtouch
When Guildsworn Prowler dies, if it wasn't blocking, draw a card.

Abyssal Hunter

{B}, {T}: Tap target creature. Abyssal Hunter deals damage equal to Abyssal Hunter's power to that creature.

Callidus Assassin

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

Whispersilk Cloak

Equipped creature can't be blocked and has shroud. (It can't be the target of spells or abilities.)
Equip {2}

Aligned Hedron Network

When Aligned Hedron Network enters the battlefield, exile all creatures with power 5 or greater until Aligned Hedron Network leaves the battlefield. (Those creatures return under their owners' control.)

Basilisk Collar

Equipped creature has deathtouch and lifelink.
Equip {2}

Feed the Swarm

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

Quietus Spike

Equipped creature has deathtouch.
Whenever equipped creature deals combat damage to a player, that player loses half their life, rounded up.
Equip {3}

Damnation

Destroy all creatures. They can't be regenerated.

Scarblade Elite

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

Dimir Guildgate

Dimir Guildgate enters the battlefield tapped.
{T}: Add {U} or {B}.

Lurking Deadeye

Flash
When Lurking Deadeye enters the battlefield, destroy target creature that was dealt damage this turn.

Cruel Sadist

{B}, {T}, Pay 1 life: Put a +1/+1 counter on Cruel Sadist.
{2}{B}, {T}, Remove X +1/+1 counters from Cruel Sadist: It deals X damage to target creature.

Vorpal Sword

Equipped creature gets +2/+0 and has deathtouch.
{5}{B}{B}{B}: Until end of turn, Vorpal Sword gains "Whenever equipped creature deals combat damage to a player, that player loses the game."
Equip {B}{B}

Undercity Eliminator

When Undercity Eliminator enters the battlefield, you may sacrifice an artifact or creature. When you do, exile target creature an opponent controls.

Command Tower

Vampire Nighthawk

Reflections of Littjara

As Reflections of Littjara enters the battlefield, choose a creature type.
Whenever you cast a spell of the chosen type, copy that spell. (A copy of a permanent spell becomes a token.)

Vanquisher's Banner

As Vanquisher's Banner enters the battlefield, choose a creature type.
Creatures you control of the chosen type get +1/+1.
Whenever you cast a creature spell of the chosen type, draw a card.

Distant Melody

Choose a creature type. Draw a card for each permanent you control of that type.

Blade of Selves

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

Reliquary Tower

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

Thorn of the Black Rose

Deathtouch
When Thorn of the Black Rose enters the battlefield, you become the monarch.

Shipwreck Marsh

Shipwreck Marsh enters the battlefield tapped unless you control two or more other lands.
{T}: Add {U} or {B}.

Doom Blade

Diabolic Tutor

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

Hunter of Eyeblights

When Hunter of Eyeblights enters the battlefield, put a +1/+1 counter on target creature you don't control.
{2}{B}, {T}: Destroy target creature with a counter on it.

Phage the Untouchable

When Phage the Untouchable enters the battlefield, if you didn't cast it from your hand, you lose the game.
Whenever Phage deals combat damage to a creature, destroy that creature. It can't be regenerated.
Whenever Phage deals combat damage to a player, that player loses the game.

Sakashima's Will

Choose one. If you control a commander as you cast this spell, you may choose both.
• Target opponent chooses a creature they control. You gain control of it.
• Choose a creature you control. Each other creature you control becomes a copy of that creature until end of turn.

Kiku, Night's Flower

{2}{B}{B}, {T}: Target creature deals damage to itself equal to its power.

Denying Wind

Search target player's library for up to seven cards and exile them. Then that player shuffles.

Shadowspear

Equipped creature gets +1/+1 and has trample and lifelink.
{1}: Permanents your opponents control lose hexproof and indestructible until end of turn.
Equip {2}

Royal Assassin

Massacre Girl

Menace
When Massacre Girl enters the battlefield, 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.

Diabolic Intent

As an additional cost to cast this spell, sacrifice a creature.
Search your library for a card, put that card into your hand, then shuffle.

In Garruk's Wake

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

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.