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 Mistblade Shinobi deals combat damage to a player, you may return target creature that player controls to its owner's hand.

Shuriken

Equipped creature has "{T}, Unattach Shuriken: Shuriken deals 2 damage to target creature. That creature's controller gains control of Shuriken unless it was unattached from a Ninja."
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

Walker of Secret Ways

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 Walker of Secret Ways deals combat damage to a player, look at that player's hand.
{1}{U}: Return target Ninja you control to its owner's hand. Activate only during your turn.

Ronin Warclub

Equipped creature gets +2/+1.
Whenever a creature you control enters, attach Ronin Warclub to that creature.
Equip {5} ({5}: Attach to target creature you control. Equip only as a sorcery.)

Minamo's Meddling

Counter target spell. That spell's controller reveals their hand, then discards each card with the same name as a card spliced onto that spell.

Minamo Sightbender

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

River Kaijin

Island

Tobita, Master of Winds

Student of Elements

When Student of Elements has flying, flip it.

Student of Elements // Tobita, Master of Winds

Mystic Restraints

Flash
Enchant creature
When Mystic Restraints enters, tap enchanted creature.
Enchanted creature doesn't untap during its controller's untap step.

Hinder

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

Tomorrow, Azami's Familiar

If you would draw a card, look at the top three cards of your library instead. Put one of those cards into your hand and the rest on the bottom of your library in any order.

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, the Still Wind 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.

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 Ninja of the Deep Hours deals combat damage to a player, you may draw a card.

Soratami Cloudskater

Flying
{2}, Return a land you control to its owner's hand: Draw a card, then discard a card.

Genju of the Falls

Enchant Island
{2}: Enchanted Island becomes a 3/2 blue Spirit creature with flying until end of turn. It's still a land.
When enchanted Island is put into a graveyard, you may return Genju of the Falls from your graveyard to your hand.

Soratami Mirror-Guard

Flying
{2}, Return a land you control to its owner's hand: Target creature with power 2 or less can't be blocked this turn.

Kaijin of the Vanishing Touch

Defender (This creature can't attack.)
Whenever Kaijin of the Vanishing Touch blocks a creature, return that creature to its owner's hand at end of combat. (Return it only if it's on the battlefield.)

Field of Reality

Enchant creature
Enchanted creature can't be blocked by Spirits.
{1}{U}: Return Field of Reality to its owner's hand.

Teardrop Kami

Sacrifice Teardrop Kami: You may tap or untap target creature.

Lifted by Clouds

Target creature gains flying until end of turn.
Splice onto Arcane {1}{U} (As you cast an Arcane spell, you may reveal this card from your hand and pay its splice cost. If you do, add this card's effects to that spell.)

Phantom Wings

Enchant creature
Enchanted creature has flying.
Sacrifice Phantom Wings: Return enchanted creature to its owner's hand.