Aether Helix

Return target permanent to its owner's hand. Return target permanent card from your graveyard to your hand.

Seeds of Renewal

Undaunted (This spell costs {1} less to cast for each opponent.)
Return up to two target cards from your graveyard to your hand. Exile Seeds of Renewal.

Arcane Signet

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

Psychic Surgery

Whenever an opponent shuffles their library, you may look at the top two cards of that library. You may exile one of those cards. Then put the rest on top of that library in any order.

Baral, Chief of Compliance

Instant and sorcery spells you cast cost {1} less to cast.
Whenever a spell or ability you control counters a spell, you may draw a card. If you do, discard a card.

Myth Unbound

Your commander costs {1} less to cast for each time it's been cast from the command zone this game.
Whenever your commander is put into the command zone from anywhere, draw a card.

Arcanis the Omnipotent

{T}: Draw three cards.
{2}{U}{U}: Return Arcanis the Omnipotent to its owner's hand.

Nylea, Keen-Eyed

Indestructible
As long as your devotion to green is less than five, Nylea isn't a creature.
Creature spells you cast cost {1} less to cast.
{2}{G}: Reveal the top card of your library. If it's a creature card, put it into your hand. Otherwise, you may put it into your graveyard.

Aethersnatch

Gain control of target spell. You may choose new targets for it. (If that spell becomes a permanent, it enters under your control.)

Azami, Lady of Scrolls

Tap an untapped Wizard you control: Draw a card.

Durnan of the Yawning Portal

Whenever Durnan attacks, look at the top four cards of your library. You may exile a creature card from among them. Put the rest on the bottom of your library in any order. For as long as that card remains exiled, you may cast it. That spell has undaunted. (It costs {1} less to cast for each opponent.)
Choose a Background (You can have a Background as a second commander.)

Sol Ring

Rashmi, Eternities Crafter

Whenever you cast your first spell each turn, reveal the top card of your library. You may cast it without paying its mana cost if it's a spell with lesser mana value. If you don't cast it, put it into your hand.

Aetherspouts

For each attacking creature, its owner puts it on their choice of the top or bottom of their library.

Back from the Brink

Exile a creature card from your graveyard and pay its mana cost: Create a token that's a copy of that card. Activate only as a sorcery.

Ghoulcaller's Bell

Aethersnipe

When Aethersnipe enters, return target nonland permanent to its owner's hand.
Evoke {1}{U}{U} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters.)

Inga and Esika

Creatures you control have vigilance and "{T}: Add one mana of any color. Spend this mana only to cast a creature spell."
Whenever you cast a creature spell, if three or more mana from creatures was spent to cast it, draw a card.

Thryx, the Sudden Storm

Flash (You may cast this spell any time you could cast an instant.)
Flying
Spells you cast with mana value 5 or greater cost {1} less to cast and can't be countered.

Sakashima of a Thousand Faces

You may have Sakashima of a Thousand Faces enter as a copy of another creature you control, except it has Sakashima of a Thousand Faces's other abilities.
The "legend rule" doesn't apply to permanents you control.
Partner (You can have two commanders if both have partner.)

Selesnya Eulogist

{2}{G}: Exile target creature card from a graveyard, then populate. (Create a token that's a copy of a creature token you control.)

Access Denied

Counter target spell. Create X 1/1 colorless Thopter artifact creature tokens with flying, where X is that spell's mana value.

Jhoira's Familiar

Flying
Historic spells you cast cost {1} less to cast. (Artifacts, legendaries, and Sagas are historic.)

Cloud Key

As Cloud Key enters, choose artifact, creature, enchantment, instant, or sorcery.
Spells you cast of the chosen type cost {1} less to cast.

Imoti, Celebrant of Bounty

Cascade (When you cast this spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom in a random order.)
Spells you cast with mana value 6 or greater have cascade.

Naiad of Hidden Coves

During turns other than yours, spells you cast cost {1} less to cast.

The Peregrine Dynamo

Haste
{1}, {T}: Copy target activated or triggered ability you control from another legendary source that's not a commander. You may choose new targets for the copy. (Mana abilities can't be targeted.)