Getting

Primordial Mist

At the beginning of your end step, you may manifest the top card of your library. (Put it onto the battlefield face down as a 2/2 creature. Turn it face up any time for its mana cost if it's a creature card.)
Exile a face-down permanent you control face up: You may play that card this turn. (You still pay its costs. Timing rules still apply.)

Stingblade Assassin

Flash
Flying
When Stingblade Assassin enters, destroy target creature an opponent controls that was dealt damage this turn.

Death in Heaven

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I, II — Target player mills two cards, then exiles their graveyard.
III — Put all creature cards exiled with Death in Heaven onto the battlefield face down under your control. They're 2/2 Cyberman artifact creatures.

Have

Open into Wonder

X target creatures can't be blocked this turn. Until end of turn, those creatures gain "Whenever this creature deals combat damage to a player, draw a card."

Skeleton Key

Equipped creature has skulk. (It can't be blocked by creatures with greater power.)
Whenever equipped creature deals combat damage to a player, you may draw a card. If you do, discard a card.
Equip {2}

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.

Eagle Vision

Freerunning {1}{U} (You may cast this spell for its freerunning cost if you dealt combat damage to a player this turn with an Assassin or commander.)
Draw three cards.

Divination

Crippling Fear

Choose a creature type. Creatures that aren't of the chosen type get -3/-3 until end of turn.

Enter the Enigma

Target creature can't be blocked this turn.
Draw a card.

Hired Poisoner

Island

Expel from Orazca

Ascend (If you control ten or more permanents, you get the city's blessing for the rest of the game.)
Return target nonland permanent to its owner's hand. If you have the city's blessing, you may put that permanent on top of its owner's library instead.

Omen Hawker

{T}: Add {C}{U}. Spend this mana only to activate abilities.

Combat Research

Enchant creature
Enchanted creature has "Whenever this creature deals combat damage to a player, draw a card."
As long as enchanted creature is legendary, it gets +1/+1 and has ward {1}. (Whenever enchanted creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {1}.)

Ruthless Ripper

Deathtouch
Morph—Reveal a black card in your hand. (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)
When Ruthless Ripper is turned face up, target player loses 2 life.

Reality Shift

Exile target creature. Its controller manifests the top card of their library. (That player puts the top card of their library onto the battlefield face down as a 2/2 creature. If it's a creature card, it can be turned face up any time for its mana cost.)

Murder

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.

Bident of Thassa

Whenever a creature you control deals combat damage to a player, you may draw a card.
{1}{U}, {T}: Creatures your opponents control attack this turn if able.

Dissolve

Counter target spell. Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Countersquall

Counter target noncreature spell. Its controller loses 2 life.

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

Scroll of Fate

{T}: Manifest a card from your hand. (Put that card onto the battlefield face down as a 2/2 creature. Turn it face up any time for its mana cost if it's a creature card.)

Negate

Royal Assassin

Misinformation

Put up to three target cards from an opponent's graveyard on top of their library in any order.

Dimir Aqueduct

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

Sign in Blood

Target player draws two cards and loses 2 life.

Arcane Signet

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

Portent

Look at the top three cards of target player's library, then put them back in any order. You may have that player shuffle.
Draw a card at the beginning of the next turn's upkeep.

Ringsight

The Ring tempts you. Search your library for a card that shares a color with a legendary creature you control, reveal it, put it into your hand, then shuffle.

Hookblade Veteran

During your turn, Hookblade Veteran has flying. (It can't be blocked except by creatures with flying or reach.)

Distant Melody

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

Ixidron

As Ixidron enters, turn all other nontoken creatures face down. (They're 2/2 creatures.)
Ixidron's power and toughness are each equal to the number of face-down creatures on the battlefield.

Sol Ring

Tetsuko Umezawa, Fugitive

Creatures you control with power or toughness 1 or less can't be blocked.

Supernatural Stamina

Until end of turn, target creature gets +2/+0 and gains "When this creature dies, return it to the battlefield tapped under its owner's control."

Command Tower

Become Anonymous

Exile target nontoken creature you own and the top two cards of your library in a face-down pile, shuffle that pile, then cloak those cards. They enter tapped. (To cloak a card, put it onto the battlefield face down as a 2/2 creature with ward {2}. Turn it face up any time for its mana cost if it's a creature card.)

Feed the Swarm

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

Poison-Blade Mentor

Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)
Whenever Poison-Blade Mentor attacks, another target Assassin you control gains deathtouch until end of turn.

Mana Leak

Counter target spell unless its controller pays {3}.

Coerced to Kill

Enchant creature
You control enchanted creature.
Enchanted creature has base power and toughness 1/1, has deathtouch, and is an Assassin in addition to its other types.

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.

Ghostform

Up to two target creatures can't be blocked this turn.

Flaying Tendrils

Devoid (This card has no color.)
All creatures get -2/-2 until end of turn. If a creature would die this turn, exile it instead.

This Town Ain't Big Enough

This spell costs {3} less to cast if it targets a permanent you control.
Return up to two target nonland permanents to their owners' hands.

Ghastly Conscription

Exile all creature cards from target player's graveyard in a face-down pile, shuffle that pile, then manifest those cards. (To manifest a card, put it onto the battlefield face down as a 2/2 creature. Turn it face up any time for its mana cost if it's a creature card.)

Rogue's Passage

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

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."

Fleeting Distraction

Target creature gets -1/-0 until end of turn.
Draw a card.

Silumgar Assassin

Creatures with power greater than Silumgar Assassin's power can't block it.
Megamorph {2}{B} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its megamorph cost and put a +1/+1 counter on it.)
When Silumgar Assassin is turned face up, destroy target creature with power 3 or less an opponent controls.

Petty Larceny

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.)
Look at the top two cards of target opponent's library and exile those cards face down. You may play those cards for as long as they remain exiled, and mana of any type can be spent to cast them. Create a Treasure token.

Panoptic Projektor

{T}: The next face-down creature spell you cast this turn costs {3} less to cast.
If turning a face-down permanent face up causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.

Agent of the Fates

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

Mothdust Changeling

Changeling (This card is every creature type.)
Tap an untapped creature you control: Mothdust Changeling gains flying until end of turn.

Unscrupulous Contractor

When Unscrupulous Contractor enters, you may sacrifice a creature. When you do, target player draws two cards and loses 2 life.
Plot {2}{B} (You may pay {2}{B} and exile this card from your hand. Cast it as a sorcery on a later turn without paying its mana cost. Plot only as a sorcery.)

Thieving Amalgam

At the beginning of each opponent's upkeep, you manifest the top card of that player's library. (Put it onto the battlefield face down as a 2/2 creature. Turn it face up any time for its mana cost if it's a creature card.)
Whenever a creature you control but don't own dies, its owner loses 2 life and you gain 2 life.

Restart Sequence

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.)
Return target creature card from your graveyard to the battlefield.

Access Tunnel

{T}: Add {C}.
{3}, {T}: Target creature with power 3 or less can't be blocked this turn.

Midnight Assassin

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

Aven Heartstabber

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

Escape Tunnel

{T}, Sacrifice Escape Tunnel: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.
{T}, Sacrifice Escape Tunnel: Target creature with power 2 or less can't be blocked this turn.

Training Grounds

Activated abilities of creatures you control cost {2} less to activate. This effect can't reduce the mana in that cost to less than one mana.

Abhorrent Oculus

As an additional cost to cast this spell, exile six cards from your graveyard.
Flying
At the beginning of each opponent's upkeep, manifest dread. (Look at the top two cards of your library. Put one onto the battlefield face down as a 2/2 creature and the other into your graveyard. Turn it face up any time for its mana cost if it's a creature card.)

Grazilaxx, Illithid Scholar

Whenever a creature you control becomes blocked, you may return it to its owner's hand.
Whenever one or more creatures you control deal combat damage to a player, draw a card.

Memory Lapse

Counter target spell. If that spell is countered this way, put it on top of its owner's library instead of into that player's graveyard.

Guildsworn Prowler

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

Ghostly Flicker

Exile two target artifacts, creatures, and/or lands you control, then return those cards to the battlefield under your control.

Tainted Isle

{T}: Add {C}.
{T}: Add {U} or {B}. Activate only if you control a Swamp.

Gloomlake Verge

{T}: Add {U}.
{T}: Add {B}. Activate only if you control an Island or a Swamp.

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.)

Sleeper's Robe

Enchant creature
Enchanted creature has fear. (It can't be blocked except by artifact creatures and/or black creatures.)
Whenever enchanted creature deals combat damage to an opponent, you may draw a card.

Talisman of Dominance

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

Double Down

Whenever you cast an outlaw spell, copy that spell. (Assassins, Mercenaries, Pirates, Rogues, and Warlocks are outlaws. Copies of permanent spells become tokens.)

Fetid Pools

({T}: Add {U} or {B}.)
Fetid Pools enters tapped.
Cycling {2} ({2}, Discard this card: Draw a card.)

Commander's Sphere

{T}: Add one mana of any color in your commander's color identity.
Sacrifice Commander's Sphere: Draw a card.

Doom Blade

Fellwar Stone

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

Swamp

Aphotic Wisps

Target creature becomes black and gains fear until end of turn. (It can't be blocked except by artifact creatures and/or black creatures.)
Draw a card.

Etrata, Deadly Fugitive

Deathtouch
Face-down creatures you control have "{2}{U}{B}: Turn this creature face up. If you can't, exile it, then you may cast the exiled card without paying its mana cost."
Whenever an Assassin you control deals combat damage to an opponent, cloak the top card of that player's library.

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.

Evie Frye

Partner with Jacob Frye (When this creature enters, target player may put Jacob into their hand from their library, then shuffle.)
{1}, {T}: Draw a card, then discard a card. When you discard a creature card this way, target creature you control can't be blocked this turn.

Exotic Orchard

Assassin Initiate

{1}: Assassin Initiate gains your choice of flying, deathtouch, or lifelink until end of turn.

Thorn of the Black Rose

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

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.)

Dimir Guildgate

This land enters tapped.
{T}: Add {U} or {B}.

Choked Estuary

As Choked Estuary enters, you may reveal an Island or Swamp card from your hand. If you don't, Choked Estuary enters tapped.
{T}: Add {U} or {B}.

Changeling Outcast

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

Mask of Riddles

Equipped creature has fear. (It can't be blocked except by artifact creatures and/or black creatures.)
Whenever equipped creature deals combat damage to a player, you may draw a card.
Equip {2}

Ezio, Blade of Vengeance

Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)
Whenever an Assassin you control deals combat damage to a player, draw a card.

Bladed Pinions

Equipped creature has flying and first strike.
Equip {2}

Lydia Frye

Lydia Frye can't be blocked by creatures with power 3 or greater.
At the beginning of your end step, surveil X, where X is the number of tapped Assassins you control. (Look at the top X cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)

Dismal Backwater

This land enters tapped.
When this land enters, you gain 1 life.
{T}: Add {U} or {B}.

Achilles Davenport

Freerunning {U}{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.)
Menace (This creature can't be blocked except by two or more creatures.)
Other Assassins you control get +1/+1.

Counterspell

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.

Sunken Hollow

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

Ravenloft Adventurer

When Ravenloft Adventurer enters, you take the initiative.
If a creature an opponent controls would die, instead exile it and put a hit counter on it.
Whenever Ravenloft Adventurer 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.

Auditore Ambush

Choose one or both —
• Return target creature to its owner's hand.
• Target player searches their library and/or graveyard for a card named Ezio, Blade of Vengeance, reveals it, and puts it into their hand. If they search their library this way, they shuffle.

Reconnaissance Mission

Whenever a creature you control deals combat damage to a player, you may draw a card.
Cycling {2} ({2}, Discard this card: Draw a card.)

Rooftop Bypass

Whenever one or more nontoken creatures you control deal combat damage to a player, create a 1/1 black Assassin creature token with menace. (It can't be blocked except by two or more creatures.)

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice Mind Stone: Draw a card.