Alora, Merry Thief

Whenever you attack, up to one target attacking creature can't be blocked this turn. Return that creature to its owner's hand at the beginning of the next end step.
Choose a Background (You can have a Background as a second commander.)

Spring-Leaf Avenger

Ninjutsu {3}{G} ({3}{G}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
Whenever Spring-Leaf Avenger deals combat damage to a player, return target permanent card from your graveyard to your hand.

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.

Island

Birds of Paradise

Vapor Snare

Enchant creature
You control enchanted creature.
At the beginning of your upkeep, sacrifice Vapor Snare unless you return a land you control to its owner's hand.

Explore

You may play an additional land this turn.
Draw a card.

Aetherize

Return all attacking creatures to their owner's hand.

Kappa Tech-Wrecker

Ninjutsu {1}{G}
Kappa Tech-Wrecker enters with a deathtouch counter on it.
Whenever Kappa Tech-Wrecker deals combat damage to a player, you may remove a deathtouch counter from it. When you do, exile target artifact or enchantment that player controls.

Zulaport Duelist

Flash
When Zulaport Duelist enters, up to one target creature gets -2/-0 until end of turn. Its controller mills two cards. (They put the top two cards of their library into their graveyard.)

Rancor

Enchant creature
Enchanted creature gets +2/+0 and has trample.
When Rancor is put into a graveyard from the battlefield, return Rancor to its owner's hand.

Ornithopter

Quickling

Flash (You may cast this spell any time you could cast an instant.)
Flying
When Quickling enters, sacrifice it unless you return another creature you control to its owner's hand.

Counterspell

Simic Charm

Choose one —
• Target creature gets +3/+3 until end of turn.
• Permanents you control gain hexproof until end of turn.
• Return target creature to its owner's hand.

Okina, Temple to the Grandfathers

{T}: Add {G}.
{G}, {T}: Target legendary creature gets +1/+1 until end of turn.

Voidslime

Counter target spell, activated ability, or triggered ability. (Mana abilities can't be targeted.)

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.

Forest

Spell Pierce

Counter target noncreature spell unless its controller pays {2}.

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 artifact: Add one mana of any color.")