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}.

Propaganda

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

Gudul Lurker

This creature can't be blocked.
Megamorph {U} (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.)

Island

Orzhov Signet

Sol Ring

Can't Stay Away

Return target creature card with mana value 3 or less from your graveyard to the battlefield. It gains "If this creature would die, exile it instead."
Flashback {3}{W}{B} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Nighteyes the Desecrator

{4}{B}: Put target creature card from a graveyard onto the battlefield under your control.

Nezumi Graverobber

{1}{B}: Exile target card from an opponent's graveyard. If no cards are in that graveyard, flip this creature.

Nezumi Graverobber // Nighteyes the Desecrator

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.

Command Tower

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

Return to the Sewers

Target creature's owner puts it on their choice of the top or bottom of their library. You create a Mutagen token. (It's an artifact with "{1}, {T}, Sacrifice this token: Put a +1/+1 counter on target creature. Activate only as a sorcery.")

Swamp

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.

Faerie Conclave

This land enters tapped.
{T}: Add {U}.
{1}{U}: This land becomes a 2/1 blue Faerie creature with flying until end of turn. It's still a land.

Slip Through Space

Devoid (This card has no color.)
Target creature can't be blocked this turn.
Draw a card.

Sakashima's Student

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.)
You may have this creature enter as a copy of any creature on the battlefield, except it's a Ninja in addition to its other creature types.

Shredder, Unrelenting

Sneak {3}{B} (You may cast this spell for {3}{B} if you also return an unblocked attacker you control to hand during the declare blockers step. He enters tapped and attacking.)
Deathtouch
Whenever Shredder enters or attacks, another target creature you control gains deathtouch until end of turn.

Brainstorm

Draw three cards, then put two cards from your hand on top of your library in any order.

Fracture

Destroy target artifact, enchantment, or planeswalker.

Revenge of Ravens

Whenever a creature attacks you or a planeswalker you control, that creature's controller loses 1 life and you gain 1 life.

Talisman of Dominance

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

Shredder's Revenge

Choose one —
• Target player discards two cards.
• Target player draws two cards and loses 2 life.

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.

Consider

Surveil 1. (Look at the top card of your library. You may put it into your graveyard.)
Draw a card.

Counterspell

Jennika, Bad Apple Big Sister

When Jennika enters, create a 2/2 red Mutant creature token.
Plainscycling {2} ({2}, Discard this card: Search your library for a Plains card, reveal it, put it into your hand, then shuffle.)

Karai's Technique

Sneak {W}{B} (You may cast this spell for {W}{B} if you also return an unblocked attacker you control to hand during the declare blockers step.)
Choose one or both —
• Target creature gets +3/+3 until end of turn.
• Target creature gets -3/-3 until end of turn.

Settle the Wreckage

Exile all attacking creatures target player controls. That player may search their library for that many basic land cards, put those cards onto the battlefield tapped, then shuffle.

Slither Blade

Nezumi Prowler

Ninjutsu {1}{B} ({1}{B}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
When this creature enters, target creature you control gains deathtouch and lifelink until end of turn.

Prehistoric Pet

This creature can't be blocked by creatures with greater power.
{1}{W}, {T}: Return another target creature you control to its owner's hand. Activate only during your turn.

Lita, Little Orphan Amphibian

Alliance — Whenever another creature you control enters, choose one that hasn't been chosen this turn.
• Put a +1/+1 counter on Lita.
• Create a Food token. (It's an artifact with "{2}, {T}, Sacrifice this token: You gain 3 life.")
• Scry 1.

Plains

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

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.

Curse of Verbosity

Enchant player
Whenever enchanted player is attacked, you draw a card. Each opponent attacking that player does the same.

Triton Shorestalker

Enter the Enigma

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

Bleachbone Verge

{T}: Add {B}.
{T}: Add {W}. Activate only if you control a Plains or a Swamp.

Arcane Signet

Leonardo, Big Brother

Sneak {W} (You may cast this spell for {W} if you also return an unblocked attacker you control to hand during the declare blockers step. He enters tapped and attacking.)
Leonardo gets +1/+0 for each other creature you control.

Dauthi Embrace

{B}{B}: Target creature gains shadow until end of turn. (It can block or be blocked by only creatures with shadow.)

Go for the Throat

Splinter, Radical Rat

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

Get Out

Choose one —
• Counter target creature or enchantment spell.
• Return one or two target creatures and/or enchantments you own to your hand.

April O'Neil, Kunoichi Trainee

When April O'Neil enters, scry 2. (Look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.)
April O'Neil can't be blocked by creatures with power 3 or greater.

Merciless Eviction

Choose one —
• Exile all artifacts.
• Exile all creatures.
• Exile all enchantments.
• Exile all planeswalkers.

Shredder's Technique

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.)
Destroy target creature or enchantment. If an enchantment was destroyed this way, you lose 2 life.

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.

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}

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.

An Offer You Can't Refuse

Counter target noncreature spell. Its controller creates two Treasure tokens. (They're artifacts with "{T}, Sacrifice this token: Add one mana of any color.")

Spirit Mantle

Enchant creature
Enchanted creature gets +1/+1 and has protection from creatures.

Chromatic Lantern

Lands you control have "{T}: Add one mana of any color."
{T}: Add one mana of any color.

Super Shredder

Menace
Whenever another permanent leaves the battlefield, put a +1/+1 counter on Super Shredder.

Assassin Gauntlet

When this Equipment enters, attach it to up to one target creature you control. Tap all creatures target opponent controls.
Equipped creature gets +1/+1 and has "Whenever this creature deals combat damage to a player, draw a card, then discard a card."
Equip {2}

Concealed Courtyard

This land enters tapped unless you control two or fewer other lands.
{T}: Add {W} or {B}.

Biting-Palm Ninja

Ninjutsu {2}{B}
This creature enters with a menace counter on it.
Whenever this creature deals combat damage to a player, you may remove a menace counter from it. When you do, that player reveals their hand and you choose a nonland card from it. Exile that card.

Changeling Outcast

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

Commander's Sphere

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

Mortify

Damn

Destroy target creature. A creature destroyed this way can't be regenerated.
Overload {2}{W}{W} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Pirated Copy

You may have this creature enter as a copy of any creature on the battlefield, except it's a Pirate in addition to its other types and it has "Whenever this creature or another creature with the same name deals combat damage to a player, you draw a card."

Despark

Exile target permanent with mana value 4 or greater.

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.