Have

Caves of Koilos

{T}: Add {C}.
{T}: Add {W} or {B}. This land deals 1 damage to you.

Talisman of Indulgence

{T}: Add {C}.
{T}: Add {B} or {R}. This artifact deals 1 damage to you.

Buried Alive

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

Orzhov Signet

Plains

Vandalblast

Destroy target artifact you don't control.
Overload {4}{R} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Interceptor, Shadow's Hound

Menace
Assassins you control have menace.
Whenever you attack with one or more legendary creatures, you may pay {2}{B}. If you do, return this card from your graveyard to the battlefield tapped and attacking.

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.

Senu, Keen-Eyed Protector

Flying, vigilance
{T}, Exile Senu: You gain 2 life and scry 2.
When a legendary creature you control attacks and isn't blocked, if this card is exiled, put it onto the battlefield attacking.

Sulfurous Springs

{T}: Add {C}.
{T}: Add {B} or {R}. This land deals 1 damage to you.

The Monarch

At the beginning of your end step, draw a card.
Whenever a creature deals combat damage to you, its controller becomes the monarch.

Big Score

As an additional cost to cast this spell, discard a card.
Draw two cards and create two Treasure tokens. (They're artifacts with "{T}, Sacrifice this token: Add one mana of any color.")

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.

Silver Shroud Costume

Flash
When this Equipment enters, attach it to target creature you control. That creature gains shroud until end of turn. (It can't be the target of spells or abilities.)
Equipped creature can't be blocked.
Equip {3}

Don't Have

Ruthless Lawbringer

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

Path of Ancestry

This land 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.)

Kelsien, the Plague

Vigilance, haste
Kelsien 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.

Rakdos Signet

Neriv, Heart of the Storm

Flying
If a creature you control that entered this turn would deal damage, it deals twice that much damage instead.

Assassin

Thrill of Possibility

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

Swamp

Warrior

Demand Answers

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

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.

Deadly Rollick

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

Arcane Signet

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

Aurelia, the Warleader

Flying, vigilance, haste
Whenever Aurelia attacks for the first time each turn, untap all creatures you control. After this phase, there is an additional combat phase.

Layla Hassan

First strike
When Layla Hassan enters and whenever one or more Assassins you control deal combat damage to a player, return target historic card from your graveyard to your hand.

Mortify

Seize the Spoils

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

Savai Triome

({T}: Add {R}, {W}, or {B}.)
This land enters tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control. It can attack and {T} no matter when it came under your control.)
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

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.)

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.

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.

Command Tower

Nomad Outpost

This land enters tapped.
{T}: Add {R}, {W}, or {B}.

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.

Seize the Day

Untap target creature. After this main phase, there is an additional combat phase followed by an additional main phase.
Flashback {2}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Vial Smasher, Gleeful Grenadier

Whenever another outlaw you control enters, Vial Smasher deals 1 damage to target opponent. (Assassins, Mercenaries, Pirates, Rogues, and Warlocks are outlaws.)

Cathartic Reunion

As an additional cost to cast this spell, discard two cards.
Draw three cards.

Olivia, Opulent Outlaw

Flying, lifelink
Whenever one or more outlaws you control deal combat damage to a player, create a Treasure token. (Assassins, Mercenaries, Pirates, Rogues, and Warlocks are outlaws.)
{3}, Sacrifice two Treasures: Put two +1/+1 counters on each creature you control. Activate only as a sorcery.

Chaos Warp

The owner of target permanent shuffles it into their library, then reveals the top card of their library. If it's a permanent card, they put it onto the battlefield.

Faithless Looting

Draw two cards, then discard two cards.
Flashback {2}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Clifftop Retreat

This land enters tapped unless you control a Mountain or a Plains.
{T}: Add {R} or {W}.

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.

Thorn of the Black Rose

Deathtouch
When this creature enters, you become the monarch.

Port Razer

Whenever this creature deals combat damage to a player, untap each creature you control. After this phase, there is an additional combat phase.
This creature can't attack a player it has already attacked this turn.

Talisman of Hierarchy

{T}: Add {C}.
{T}: Add {W} or {B}. This artifact deals 1 damage to you.

Isolated Chapel

This land enters tapped unless you control a Plains or a Swamp.
{T}: Add {W} or {B}.

Reconnaissance

{0}: Remove target attacking creature you control from combat and untap it. (If you activate during end of combat, the creature will untap after it deals combat damage.)

Virtus the Veiled

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

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 this creature enters, you draw a card and you lose 1 life.

Altaïr Ibn-La'Ahad

First strike
Whenever Altaïr 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.

Conspiracy

As this enchantment enters, choose a creature type.
Creatures you control are the chosen type. The same is true for creature spells you control and creature cards you own that aren't on the battlefield.

Overpowering Attack

Freerunning {2}{R} (You may cast this spell for its freerunning cost if you dealt combat damage to a player this turn with an Assassin or commander.)
Untap all creatures you control that attacked this turn. If it's your main phase, there is an additional combat phase after this phase, followed by an additional main phase.

Battlefield Forge

{T}: Add {C}.
{T}: Add {R} or {W}. This land deals 1 damage to you.

Talisman of Conviction

{T}: Add {C}.
{T}: Add {R} or {W}. This artifact deals 1 damage to you.

Zurgo Stormrender

Mobilize 1 (Whenever this creature attacks, create a tapped and attacking 1/1 red Warrior creature token. Sacrifice it at the beginning of the next end step.)
Whenever a creature token you control leaves the battlefield, draw a card if it was attacking. Otherwise, each opponent loses 1 life.

Secluded Courtyard

As this land 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.

Arno Dorian

Deathtouch
Other Assassins you control get +2/+0.
Disguise {B}{R} (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.)

Midnight Assassin

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

Brotherhood Regalia

Equipped creature has ward {2}, is an Assassin in addition to its other types, and can't be blocked.
Equip legendary creature {1}
Equip {3} ({3}: Attach to target creature you control. Equip only as a sorcery.)

Vincent, Vengeful Atoner

Menace
Whenever one or more creatures you control deal combat damage to a player, put a +1/+1 counter on Vincent.
Chaos — Whenever Vincent deals combat damage to an opponent, it deals that much damage to each other opponent if Vincent's power is 7 or greater.

Grab the Prize

As an additional cost to cast this spell, discard a card.
Draw two cards. If the discarded card wasn't a land card, Grab the Prize deals 2 damage to each opponent.

Shadow, Mysterious Assassin

Deathtouch
Throw — Whenever Shadow deals combat damage to a player, you may sacrifice another nonland permanent. If you do, draw two cards and each opponent loses life equal to the mana value of the sacrificed permanent.

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.

Menace (This creature can't be blocked except by two or more creatures.)

Mountain

Blasphemous Act

This spell costs {1} less to cast for each creature on the battlefield.
Blasphemous Act deals 13 damage to each creature.

Ashes of the Fallen

As this artifact enters, choose a creature type.
Each creature card in your graveyard has the chosen creature type in addition to its other types.

Massacre Girl, Known Killer

Menace
Creatures you control have wither. (They deal damage to creatures in the form of -1/-1 counters.)
Whenever a creature an opponent controls dies, if its toughness was less than 1, draw a card.

Soldier

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 deals damage equal to the number of creature tokens you control to target opponent.

Arbaaz Mir

Whenever Arbaaz Mir or another nontoken historic permanent you control enters, Arbaaz Mir deals 1 damage to each opponent and you gain 1 life. (Artifacts, legendaries, and Sagas are historic.)

Final Showdown

Spree (Choose one or more additional costs.)
+ {1} — All creatures lose all abilities until end of turn.
+ {1} — Choose a creature you control. It gains indestructible until end of turn.
+ {3}{W}{W} — Destroy all creatures.

Purphoros, God of the Forge

Indestructible
As long as your devotion to red is less than five, Purphoros isn't a creature.
Whenever another creature you control enters, Purphoros deals 2 damage to each opponent.
{2}{R}: Creatures you control get +1/+0 until end of turn.

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.)

Smoldering Marsh

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

Final Parting

Search your library for two cards. Put one into your hand and the other into your graveyard. Then shuffle.

Phobos

Copy

(This token can be used to represent a token that's a copy of a permanent.)

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.

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}

Tormenting Voice

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.)

Herald's Horn

As this artifact enters, choose a creature type.
Creature spells you cast of the chosen type cost {1} less to cast.
At the beginning of your upkeep, look at the top card of your library. If it's a creature card of the chosen type, you may reveal it and put it into your hand.

Terminate

Destroy target creature. It can't be regenerated.

Dragonskull Summit

This land enters tapped unless you control a Swamp or a Mountain.
{T}: Add {B} or {R}.

Gamble

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

Impact Tremors

Whenever a creature you control enters, this enchantment deals 1 damage to each opponent.

Lightning Greaves

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

The Master, Multiplied

Myriad
The "legend rule" doesn't apply to creature tokens you control.
Triggered abilities you control can't cause you to sacrifice or exile creature tokens you control.