Blacksmith's Skill

Target permanent gains hexproof and indestructible until end of turn. If it's an artifact creature, it gets +2/+2 until end of turn.

Bayek of Siwa

Double strike
During your turn, other historic creatures you control have double strike.
Disguise {1}{R}{W} (You may cast this card face down for {3} as a 2/2 creature with ward {2}. Turn it face up any time for its disguise cost.)

Sunfall

Exile all creatures. Incubate X, where X is the number of creatures exiled this way. (Create an Incubator token with X +1/+1 counters on it and "{2}: Transform this artifact." It transforms into a 0/0 Phyrexian artifact creature.)

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.

At Knifepoint

During your turn, outlaws you control have first strike. (Assassins, Mercenaries, Pirates, Rogues, and Warlocks are outlaws.)
Whenever you commit a crime, create a 1/1 red Mercenary creature token with "{T}: Target creature you control gets +1/+0 until end of turn. Activate only as a sorcery." This ability triggers only once each turn.

Altaïr Ibn-La'Ahad

First strike
Whenever Altaïr Ibn-La'Ahad attacks, exile up to one target Assassin creature card from your graveyard with a memory counter on it. Then for each creature card you own in exile with a memory counter on it, create a tapped and attacking token that's a copy of it. Exile those tokens at end of combat.

Buried Alive

Search your library for up to three creature cards, put them into your graveyard, then shuffle.

Swamp

Scoured Barrens

Scoured Barrens enters tapped.
When Scoured Barrens enters, you gain 1 life.
{T}: Add {W} or {B}.

Shambling Vent

Shambling Vent enters tapped.
{T}: Add {W} or {B}.
{1}{W}{B}: Shambling Vent becomes a 2/3 white and black Elemental creature with lifelink until end of turn. It's still a land.

Haystack

{2}, {T}: Target creature you control phases out. (Treat it and anything attached to it as though they don't exist until your next turn.)

Despark

Exile target permanent with mana value 4 or greater.

Sol Ring

Secluded Courtyard

As Secluded Courtyard enters, choose a creature type.
{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a creature spell of the chosen type or activate an ability of a creature source of the chosen type.

Isshin, Two Heavens as One

If a creature attacking causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.

Caesar, Legion's Emperor

Whenever you attack, you may sacrifice another creature. When you do, choose two —
• Create two 1/1 red and white Soldier creature tokens with haste that are tapped and attacking.
• You draw a card and you lose 1 life.
• Caesar, Legion's Emperor deals damage equal to the number of creature tokens you control to target opponent.

Hidden Blade

Flash
When Hidden Blade enters, attach it to target creature you control. If that creature is an Assassin, it gains deathtouch until end of turn.
Equipped creature gets +1/+0 and has first strike.
Equip {2}

Nazgûl Battle-Mace

Equipped creature has menace, deathtouch, annihilator 1, and "Whenever an opponent sacrifices a nontoken permanent, put that card onto the battlefield under your control unless that player pays 3 life." (Whenever a creature with annihilator 1 attacks, defending player sacrifices a permanent.)
Equip {3}

Demand Answers

As an additional cost to cast this spell, sacrifice an artifact or discard a card.
Draw two cards.

Bloodfell Caves

Bloodfell Caves enters tapped.
When Bloodfell Caves enters, you gain 1 life.
{T}: Add {B} or {R}.

Cemetery Tampering

Hideaway 5 (When this enchantment enters, look at the top five cards of your library, exile one face down, then put the rest on the bottom in a random order.)
At the beginning of your upkeep, you may mill three cards. Then if there are twenty or more cards in your graveyard, you may play the exiled card without paying its mana cost.

Desolate Mire

Éomer, Marshal of Rohan

Haste
Whenever one or more other attacking legendary creatures you control die, untap all creatures you control. After this phase, there is an additional combat phase. This ability triggers only once each turn.

Inherited Envelope

When Inherited Envelope enters, the Ring tempts you.
{T}: Add one mana of any color.

Deadly Dispute

As an additional cost to cast this spell, sacrifice an artifact or creature.
Draw two cards and create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Basilisk Collar

Equipped creature has deathtouch and lifelink.
Equip {2}

Age-Graced Chapel

Age-Graced Chapel enters tapped.
{T}: Add {W} or {B}.

Glasswing Grace

Enchant creature
Enchanted creature gets +2/+2 and has flying and lifelink.

Glasswing Grace // Age-Graced Chapel

Sanguine Morass

Sanguine Morass enters tapped.
{T}: Add {B} or {R}.

Bloodsoaked Insight

This spell costs {1} less to cast for each 1 life your opponents have lost this turn.
Target opponent exiles the top three cards of their library. Until the end of your next turn, you may play those cards. If you cast a spell this way, mana of any type can be spent to cast it.

Bloodsoaked Insight // Sanguine Morass

Royal Assassin

Ashen Rider

Flying
When Ashen Rider enters or dies, exile target permanent.

Restless Vents

Restless Vents enters tapped.
{T}: Add {B} or {R}.
{1}{B}{R}: Until end of turn, Restless Vents becomes a 2/3 black and red Insect creature with menace. It's still a land.
Whenever Restless Vents attacks, you may discard a card. If you do, draw a card.

Whispersilk Cloak

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

Merciless Harlequin

Freerunning {1}{B} (You may cast this spell for its freerunning cost if you dealt combat damage to a player this turn with an Assassin or commander.)
When Merciless Harlequin enters, you draw a card and you lose 1 life.

Ripples of Undeath

At the beginning of your first main phase, mill three cards. Then you may pay {1} and 3 life. If you do, put a card from among those cards into your hand.

Arcane Signet

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

Undercity Eliminator

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

Thorn of the Black Rose

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

Kelsien, the Plague

Vigilance, haste
Kelsien, the Plague gets +1/+1 for each experience counter you have.
{T}: Kelsien deals 1 damage to target creature you don't control. When that creature dies this turn, you get an experience counter.

The Animus

At the beginning of your end step, exile up to one target legendary creature card from a graveyard with a memory counter on it.
{T}: Until your next turn, target legendary creature you control becomes a copy of target creature card in exile with a memory counter on it. Activate only as a sorcery.

Austere Command

Choose two —
• Destroy all artifacts.
• Destroy all enchantments.
• Destroy all creatures with mana value 3 or less.
• Destroy all creatures with mana value 4 or greater.

Vile Entomber

Deathtouch
When Vile Entomber enters, search your library for a card, put that card into your graveyard, then shuffle.

Legion Stronghold

Legion Stronghold enters tapped.
{T}: Add {R} or {W}.

Legion Leadership

Until end of turn, double target creature's power and it gains first strike.

Legion Leadership // Legion Stronghold

Murderous Redcap

When Murderous Redcap enters, it deals damage equal to its power to any target.
Persist (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.)

Guildsworn Prowler

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

The Spear of Leonidas

Whenever equipped creature attacks, choose one —
• Bull Rush — It gains double strike until end of turn.
• Summon — Create Phobos, a legendary 3/2 red Horse creature token.
• Revelation — Discard two cards, then draw two cards.
Equip {2}

Talisman of Indulgence

{T}: Add {C}.
{T}: Add {B} or {R}. Talisman of Indulgence deals 1 damage to you.

Anguished Unmaking

Exile target nonland permanent. You lose 3 life.

Oriq Loremage

{T}: Search your library for a card, put it into your graveyard, then shuffle. If it's an instant or sorcery card, put a +1/+1 counter on Oriq Loremage.

Wind-Scarred Crag

Wind-Scarred Crag enters tapped.
When Wind-Scarred Crag enters, you gain 1 life.
{T}: Add {R} or {W}.

Desmond Miles

Menace
Desmond Miles gets +1/+0 for each other Assassin you control and each Assassin card in your graveyard.
Whenever Desmond Miles deals combat damage to a player, surveil X, where X is the amount of damage it dealt to that player.

Boros Guildgate

Boros Guildgate enters tapped.
{T}: Add {R} or {W}.

Nasty End

As an additional cost to cast this spell, sacrifice a creature.
Draw two cards. If the sacrificed creature was legendary, draw three cards instead.

Kassandra, Eagle Bearer

Haste
When Kassandra enters, search your graveyard, hand, and library for a card named The Spear of Leonidas, put it onto the battlefield, then shuffle.
Whenever a creature you control with a legendary Equipment attached to it deals combat damage to a player, draw a card.

Rising of the Day

Creatures you control have haste.
Legendary creatures you control get +1/+0.

Queen Marchesa

Deathtouch, haste
When Queen Marchesa enters, you become the monarch.
At the beginning of your upkeep, if an opponent is the monarch, create a 1/1 black Assassin creature token with deathtouch and haste.

Rogue's Passage

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

Merciless Resolve

As an additional cost to cast this spell, sacrifice a creature or land.
Draw two cards.

Ruthless Lawbringer

When Ruthless Lawbringer enters, you may sacrifice another creature. When you do, destroy target nonland permanent.

Brotherhood Headquarters

{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast an Assassin spell or a spell that has freerunning, or to activate an ability of an Assassin source.

Mythos of Snapdax

Each player chooses an artifact, a creature, an enchantment, and a planeswalker from among the nonland permanents they control, then sacrifices the rest. If {B}{R} was spent to cast this spell, you choose the permanents for each player instead.

Path to Exile

Exile target creature. Its controller may search their library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Mortify

Roshan, Hidden Magister

Other creatures you control are Assassins in addition to their other types. The same is true for creature spells you control and creature cards you own that aren't on the battlefield.
Face-down creatures you control have menace.
Whenever a permanent you control is turned face up, you draw a card and you lose 1 life.

Your Temple Is Under Attack

Choose one —
• Pray for Protection — Creatures you control gain indestructible until end of turn.
• Strike a Deal — You and target opponent each draw two cards.

Foreboding Ruins

As Foreboding Ruins enters, you may reveal a Swamp or Mountain card from your hand. If you don't, Foreboding Ruins enters tapped.
{T}: Add {B} or {R}.

Shay Cormac

{1}: Permanents your opponents control lose hexproof, indestructible, protection, shroud, and ward until end of turn.
Whenever a creature an opponent controls becomes the target of a spell or ability you control, put a bounty counter on that creature.
Whenever a creature with a bounty counter on it dies, put two +1/+1 counters on Shay Cormac.

Hostile Negotiations

Exile the top three cards of your library in a face-down pile, then exile the top three cards of your library in another face-down pile. Look at the cards in each pile, then turn a pile of your choice face up. An opponent chooses one of those piles. Put that pile into your hand and the other into your graveyard. You lose 3 life.

Swords to Plowshares

Exile target creature. Its controller gains life equal to its power.

Stinkweed Imp

Flying
Whenever Stinkweed Imp deals combat damage to a creature, destroy that creature.
Dredge 5 (If you would draw a card, you may mill five cards instead. If you do, return this card from your graveyard to your hand.)

Drossforge Bridge

Drossforge Bridge enters tapped.
Indestructible
{T}: Add {B} or {R}.

Temple of Malice

Temple of Malice enters tapped.
When Temple of Malice enters, scry 1.
{T}: Add {B} or {R}.

Command Tower

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}

Mountain

Path of Ancestry

Path of Ancestry enters tapped.
{T}: Add one mana of any color in your commander's color identity. When that mana is spent to cast a creature spell that shares a creature type with your commander, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Aya of Alexandria

Menace, lifelink
Whenever a historic creature you control deals combat damage to a player, create a 1/1 black Assassin creature token with menace. (Artifacts, legendaries, and Sagas are historic.)

Nomad Outpost

Nomad Outpost enters tapped.
{T}: Add {R}, {W}, or {B}.

Breathe Your Last

Destroy target creature or planeswalker. You gain 1 life for each of its colors.

Recruiter of the Guard

When Recruiter of the Guard enters, you may search your library for a creature card with toughness 2 or less, reveal it, put it into your hand, then shuffle.

Théoden, King of Rohan

Whenever Théoden, King of Rohan or another Human you control enters, target creature gains double strike until end of turn.

Nekrataal

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

Ash Barrens

{T}: Add {C}.
Basic landcycling {1} ({1}, Discard this card: Search your library for a basic land card, reveal it, put it into your hand, then shuffle.)