Dour Port-Mage

Whenever one or more other creatures you control leave the battlefield without dying, draw a card.
{1}{U}, {T}: Return another target creature you control to its owner's hand.

Archaeomancer

When Archaeomancer enters, return target instant or sorcery card from your graveyard to your hand.

Island

Ephemerate

Exile target creature you control, then return it to the battlefield under its owner's control.
Rebound (If you cast this spell from your hand, exile it as it resolves. At the beginning of your next upkeep, you may cast this card from exile without paying its mana cost.)

Arcane Signet

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

Niko, Light of Hope

When Niko, Light of Hope enters, create two Shard tokens. (They're enchantments with "{2}, Sacrifice this enchantment: Scry 1, then draw a card.")
{2}, {T}: Exile target nonlegendary creature you control. Shards you control become copies of it until the beginning of the next end step. Return it to the battlefield under its owner's control at the beginning of the next end step.

Cloudshift

Exile target creature you control, then return that card to the battlefield under your control.

Archmage of Echoes

Flying, ward {2}
Whenever you cast a Faerie or Wizard permanent spell, copy it. (The copy becomes a token.)

Naban, Dean of Iteration

If a Wizard you control entering causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.

Curiosity Crafter

Flying
You have no maximum hand size.
Whenever a creature token you control deals combat damage to a player, draw a card.

Reflector Mage

When Reflector Mage enters, return target creature an opponent controls to its owner's hand. That creature's owner can't cast spells with the same name as that creature until your next turn.

Command Tower

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.

Eerie Interlude

Exile any number of target creatures you control. Return those cards to the battlefield under their owner's control at the beginning of the next end step.

Swords to Plowshares

Exile target creature. Its controller gains life equal to its power.

Far Traveler

Commander creatures you own have "At the beginning of your end step, exile up to one target tapped creature you control, then return it to the battlefield under its owner's control."

Niko Aris

When Niko Aris enters, create X Shard tokens. (They're enchantments with "{2}, Sacrifice this enchantment: Scry 1, then draw a card.")
+1: Up to one target creature you control can't be blocked this turn. Whenever that creature deals damage this turn, return it to its owner's hand.
−1: Niko Aris deals 2 damage to target tapped creature for each card you've drawn this turn.
−1: Create a Shard token.

Plains

Strionic Resonator

{2}, {T}: Copy target triggered ability you control. You may choose new targets for the copy. (A triggered ability uses the words "when," "whenever," or "at.")

Aether Channeler

When Aether Channeler enters, choose one —
• Create a 1/1 white Bird creature token with flying.
• Return another target nonland permanent to its owner's hand.
• Draw a card.

Preston, the Vanisher

Whenever another nontoken creature you control enters, if it wasn't cast, create a token that's a copy of that creature, except it's a 0/1 white Illusion.
{1}{W}, Sacrifice five Illusions: Exile target nonland permanent.

Sol Ring

Essence Flux

Exile target creature you control, then return that card to the battlefield under its owner's control. If it's a Spirit, put a +1/+1 counter on it.