Command Tower

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

Throat Slitter

Ninjutsu {2}{B} ({2}{B}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
Whenever this creature deals combat damage to a player, destroy target nonblack creature that player controls.

Fetid Heath

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

Krang & Shredder

Whenever Krang & Shredder enter or attack, each opponent exiles cards from the top of their library until they exile a nonland card.
Disappear — At the beginning of your end step, if a permanent left the battlefield under your control this turn, you may cast a card exiled with Krang & Shredder without paying its mana cost.

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.

Counterspell

Slither Blade

Underground River

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

Moon-Circuit Hacker

Ninjutsu {U} ({U}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
Whenever this creature deals combat damage to a player, you may draw a card. If you do, discard a card unless this creature entered this turn.

The Blue Spirit

You may cast the first creature spell you cast each turn as though it had flash.
Whenever a nontoken creature you control enters during combat, draw a card.

Orzhov Signet

Splinter, Hamato Yoshi

Sneak {B} (You may cast this spell for {B} if you also return an unblocked attacker you control to hand during the declare blockers step. He enters tapped and attacking.)
Menace (This creature can't be blocked except by two or more creatures.)
Other Ninjas you control get +1/+1.

Ingenious Infiltrator

Ninjutsu {U}{B} ({U}{B}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
Whenever a Ninja you control deals combat damage to a player, draw a card.

Shark Shredder, Killer Clone

Sneak {3}{B}{B}
First strike
Whenever Shark Shredder deals combat damage to a player, put up to one target creature card from that player's graveyard onto the battlefield under your control. It enters tapped and attacking that player.

Satoru, the Infiltrator

Menace
Whenever Satoru and/or one or more other nontoken creatures you control enter, if none of them were cast or no mana was spent to cast them, draw a card.

Swan Song

Counter target enchantment, instant, or sorcery spell. Its controller creates a 2/2 blue Bird creature token with flying.

Azorius Signet

Prosperous Thief

Ninjutsu {1}{U} ({1}{U}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
Whenever one or more Ninja or Rogue creatures you control deal combat damage to a player, create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Plains

Kamiz, Obscura Oculus

Whenever you attack, target attacking creature can't be blocked this turn. It connives. Then choose another attacking creature with lesser power. That creature gains double strike until end of turn. (To have a creature connive, draw a card, then discard a card. If you discarded a nonland card, put a +1/+1 counter on that creature.)

Ninja of the Deep Hours

Ninjutsu {1}{U} ({1}{U}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
Whenever this creature deals combat damage to a player, you may draw a card.

Yuriko, the Tiger's Shadow

Commander ninjutsu {U}{B} ({U}{B}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand or the command zone tapped and attacking.)
Whenever a Ninja you control deals combat damage to a player, reveal the top card of your library and put that card into your hand. Each opponent loses life equal to that card's mana value.

Smoke Shroud

Enchant creature
Enchanted creature gets +1/+1 and has flying.
When a Ninja you control enters, you may return this card from your graveyard to the battlefield attached to that creature.

Fallen Shinobi

Ninjutsu {2}{U}{B} ({2}{U}{B}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
Whenever this creature deals combat damage to a player, that player exiles the top two cards of their library. Until end of turn, you may play those cards without paying their mana costs.

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.)

Splinter, Radical Rat

If an ability of a Ninja creature you control triggers, that ability triggers an additional time.
{1}{U}: Target Ninja can't be blocked this turn.

Pongify

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

Orochi Soul-Reaver

Ninjutsu {3}{B} ({3}{B}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
Whenever one or more creatures you control deal combat damage to a player, create a Treasure token and 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.)

Propaganda

Creatures can't attack you unless their controller pays {2} for each creature they control that's attacking you.

Lightning Greaves

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

Exotic Orchard

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

Silver-Fur Master

Ninjutsu {U}{B} ({U}{B}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
Ninjutsu abilities you activate cost {1} less to activate.
Other Ninja and Rogue creatures you control get +1/+1.

Satoru Umezawa

Whenever you activate a ninjutsu ability, look at the top three cards of your library. Put one of them into your hand and the rest on the bottom of your library in any order. This ability triggers only once each turn.
Each creature card in your hand has ninjutsu {2}{U}{B}.

Ink-Eyes, Servant of Oni

Ninjutsu {3}{B}{B} ({3}{B}{B}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
Whenever Ink-Eyes deals combat damage to a player, you may put target creature card from that player's graveyard onto the battlefield under your control.
{1}{B}: Regenerate Ink-Eyes.

Changeling Outcast

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

Glacial Fortress

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

Moonsnare Specialist

Ninjutsu {2}{U} ({2}{U}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
When this creature enters, return up to one target creature to its owner's hand.

Arm with Aether

Until end of turn, creatures you control gain "Whenever this creature deals damage to an opponent, you may return target creature that player controls to its owner's hand."

Sol Ring

Port Town

As this land enters, you may reveal a Plains or Island card from your hand. If you don't, this land enters tapped.
{T}: Add {W} or {U}.

Arcane Signet

Silent-Blade Oni

Ninjutsu {4}{U}{B} ({4}{U}{B}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
Whenever this creature deals combat damage to a player, look at that player's hand. You may cast a spell from among those cards without paying its mana cost.

Thousand-Faced Shadow

Ninjutsu {2}{U}{U} ({2}{U}{U}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
Flying
When this creature enters from your hand, if it's attacking, create a token that's a copy of another target attacking creature. The token enters tapped and attacking.

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}.)

Oroku Saki, Shredder Rising

Sneak {1}{B} (You may cast this spell for {1}{B} if you also return an unblocked attacker you control to hand during the declare blockers step. He enters tapped and attacking.)
Whenever Oroku Saki deals combat damage to a player, you draw a card and lose 1 life.

Kindred Discovery

As this enchantment enters, choose a creature type.
Whenever a creature you control of the chosen type enters or attacks, draw a card.

Throatseeker

Unblocked attacking Ninjas you control have lifelink.

Desolate Mire

Swamp

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.

Fellwar Stone

Choked Estuary

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

Endless Foot Assault

Squad {1}{W} (As an additional cost to cast this spell, you may pay {1}{W} any number of times. When this enchantment enters, create that many tokens that are copies of it.)
Whenever you attack, for each opponent, create a 1/1 black Ninja creature token that's tapped and attacking that player.

Baleful Strix

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

Mist-Syndicate Naga

Ninjutsu {2}{U} ({2}{U}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
Whenever this creature deals combat damage to a player, create a token that's a copy of this creature.

Island

Darkwater Catacombs

Gossip's Talent

(Gain the next level as a sorcery to add its ability.)
Whenever a creature you control enters, surveil 1.
{1}{U}: Level 2
Whenever you attack, target attacking creature with power 3 or less can't be blocked this turn.
{3}{U}: Level 3
Whenever a creature you control deals combat damage to a player, you may exile it, then return it to the battlefield under its owner's control.

Cover of Darkness

As this enchantment enters, choose a creature type.
Creatures of the chosen type have fear. (They can't be blocked except by artifact creatures and/or black creatures.)

Leonardo's Technique

Sneak {1}{W} (You may cast this spell for {1}{W} if you also return an unblocked attacker you control to hand during the declare blockers step.)
Return one or two target creature cards each with mana value 3 or less from your graveyard to the battlefield.

Higure, the Still Wind

Ninjutsu {2}{U}{U} ({2}{U}{U}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
Whenever Higure deals combat damage to a player, you may search your library for a Ninja card, reveal it, put it into your hand, then shuffle.
{2}: Target Ninja creature can't be blocked this turn.

Drowned Catacomb

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

Karai, Future of the Foot

Sneak {2}{W}{B} (You may cast this spell for {2}{W}{B} if you also return an unblocked attacker you control to hand during the declare blockers step. She enters tapped and attacking.)
Whenever Karai deals combat damage to a player, return target creature card from your graveyard to your hand. If her sneak cost was paid this turn, instead return that card to the battlefield.

Turncoat Kunoichi

Sneak {2}{W}{B} (You may cast this spell for {2}{W}{B} if you also return an unblocked attacker you control to hand during the declare blockers step. It enters tapped and attacking.)
When this creature enters, choose target creature an opponent controls. Exile that creature until this creature leaves the battlefield. If this creature's sneak cost was paid, instead exile the chosen creature.

Siren Stormtamer

Flying
{U}, Sacrifice this creature: Counter target spell or ability that targets you or a creature you control.

Silent Hallcreeper

This creature can't be blocked.
Whenever this creature deals combat damage to a player, choose one that hasn't been chosen —
• Put two +1/+1 counters on this creature.
• Draw a card.
• This creature becomes a copy of another target creature you control.

Nashi, Moon Sage's Scion

Ninjutsu {3}{B} ({3}{B}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
Whenever Nashi deals combat damage to a player, exile the top card of each player's library. Until end of turn, you may play one of those cards. If you cast a spell this way, pay life equal to its mana value rather than paying its mana cost.

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.

Negate

Dark Leo & Shredder

Sneak {W}{B}
Attacking Ninjas you control have deathtouch.
Whenever Dark Leo & Shredder deal combat damage to a player, create a 1/1 black Ninja creature token. Then if you control five or more Ninjas, that player loses half their life, rounded up.

Ninja Teen

(Gain the next level as a sorcery to add its ability.)
Whenever a creature you control leaves the battlefield, each opponent loses 1 life.
{1}{B}: Level 2
Creatures you control get +1/+0 and have menace.
{B}: Level 3
Creature cards in your graveyard have sneak {3}{B}.
You may cast creature spells from your graveyard using their sneak abilities.

Splinter, Aging Champion

When Splinter enters, destroy up to one target tapped creature.
When Splinter leaves the battlefield, you and another target player each draw a card.

Arcane Sanctum

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

Mistblade Shinobi

Ninjutsu {U} ({U}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
Whenever this creature deals combat damage to a player, you may return target creature that player controls to its owner's hand.

Splinter's Technique

Sneak {1}{B} (You may cast this spell for {1}{B} if you also return an unblocked attacker you control to hand during the declare blockers step.)
Search your library for a card, put that card into your hand, then shuffle.

Patchwork Banner

As this artifact enters, choose a creature type.
Creatures you control of the chosen type get +1/+1.
{T}: Add one mana of any color.

Turtle Lair

{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a Ninja or Turtle spell.
{3}, {T}: Target Ninja or Turtle can't be blocked this turn.

Shredder, Shadow Master

Whenever Shredder attacks a player, for each other opponent, create a token that's a copy of Shredder tapped and attacking that player, except it isn't legendary. Sacrifice those tokens at end of combat.
Whenever Shredder deals combat damage to a player, that player loses half their life, rounded up.

Isolated Chapel

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

Sunken Hollow

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