Pako, Arcane Retriever

Partner with Haldan, Avid Arcanist
Haste
Whenever Pako, Arcane Retriever attacks, exile the top card of each player's library and put a fetch counter on each of them. Put a +1/+1 counter on Pako for each noncreature card exiled this way.

Kibo, Uktabi Prince

{T}: Each player creates a colorless artifact token named Banana with "{T}, Sacrifice this artifact: Add {R} or {G}. You gain 2 life."
Whenever an artifact an opponent controls is put into a graveyard from the battlefield, put a +1/+1 counter on each creature you control that's an Ape or a Monkey.
Whenever Kibo attacks, defending player sacrifices an artifact of their choice.

The Ur-Dragon

Eminence — As long as The Ur-Dragon is in the command zone or on the battlefield, other Dragon spells you cast cost {1} less to cast.
Flying
Whenever one or more Dragons you control attack, draw that many cards, then you may put a permanent card from your hand onto the battlefield.

Rograkh, Son of Rohgahh

First strike, menace, trample
Partner (You can have two commanders if both have partner.)

Mishra, Claimed by Gix

Whenever you attack, each opponent loses X life and you gain X life, where X is the number of attacking creatures. If Mishra, Claimed by Gix and a creature named Phyrexian Dragon Engine are attacking, and you both own and control them, exile them, then meld them into Mishra, Lost to Phyrexia. It enters tapped and attacking.

Sisay, Weatherlight Captain

Sisay, Weatherlight Captain gets +1/+1 for each color among other legendary permanents you control.
{W}{U}{B}{R}{G}: Search your library for a legendary permanent card with mana value less than Sisay's power, put that card onto the battlefield, then shuffle.

Arahbo, Roar of the World

Eminence — At the beginning of combat on your turn, if Arahbo, Roar of the World is in the command zone or on the battlefield, another target Cat you control gets +3/+3 until end of turn.
Whenever another Cat you control attacks, you may pay {1}{G}{W}. If you do, it gains trample and gets +X/+X until end of turn, where X is its power.

Magus Lucea Kane

Spiritual Leader — At the beginning of combat on your turn, put a +1/+1 counter on target creature.
Psychic Stimulus — {T}: Add {C}{C}. When you next cast a spell with {X} in its mana cost or activate an ability with {X} in its activation cost this turn, copy that spell or ability. You may choose new targets for the copy. (A copy of a permanent spell becomes a token.)

Lord Windgrace

+2: Discard a card, then draw a card. If a land card is discarded this way, draw an additional card.
−3: Return up to two target land cards from your graveyard to the battlefield.
−11: Destroy up to six target nonland permanents, then create six 2/2 green Cat Warrior creature tokens with forestwalk.
Lord Windgrace can be your commander.

Jodah, the Unifier

Legendary creatures you control get +X/+X, where X is the number of legendary creatures you control.
Whenever you cast a legendary spell from your hand, exile cards from the top of your library until you exile a legendary nonland card with lesser mana value. You may cast that card without paying its mana cost. Put the rest on the bottom of your library in a random order.

Teysa Karlov

If a creature dying causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.
Creature tokens you control have vigilance and lifelink.

Beledros Witherbloom

Flying
At the beginning of each upkeep, create a 1/1 black and green Pest creature token with "When this creature dies, you gain 1 life."
Pay 10 life: Untap all lands you control. Activate only once each turn.

Yennett, Cryptic Sovereign

Flying, vigilance, menace
Whenever Yennett, Cryptic Sovereign attacks, reveal the top card of your library. You may cast it without paying its mana cost if its mana value is odd. If you don't cast it, draw a card.

Gishath, Sun's Avatar

Vigilance, trample, haste
Whenever Gishath, Sun's Avatar deals combat damage to a player, reveal that many cards from the top of your library. Put any number of Dinosaur creature cards from among them onto the battlefield and the rest on the bottom of your library in a random order.

Tetsuo, Imperial Champion

Whenever Tetsuo, Imperial Champion attacks, if it's equipped, choose one —
• Tetsuo deals damage equal to the highest mana value among Equipment attached to it to any target.
• You may cast an instant or sorcery spell from your hand with mana value less than or equal to the highest mana value among Equipment attached to Tetsuo without paying its mana cost.

Sefris of the Hidden Ways

Whenever one or more creature cards are put into your graveyard from anywhere, venture into the dungeon. This ability triggers only once each turn. (To venture into the dungeon, enter the first room or advance to the next room.)
Create Undead — Whenever you complete a dungeon, return target creature card from your graveyard to the battlefield.

Isu the Abominable

You may look at the top card of your library any time.
You may play snow lands and cast snow spells from the top of your library.
Whenever another snow permanent you control enters, you may pay {G}, {W}, or {U}. If you do, put a +1/+1 counter on Isu the Abominable.

Haldan, Avid Arcanist

Partner with Pako, Arcane Retriever (When this creature enters, target player may put Pako into their hand from their library, then shuffle.)
You may play lands and cast noncreature spells from among cards you exiled that have fetch counters on them, and you may spend mana as though it were mana of any color to cast those spells.

Ardenn, Intrepid Archaeologist

At the beginning of combat on your turn, you may attach any number of Auras and Equipment you control to target permanent or player.
Partner (You can have two commanders if both have partner.)

Rocco, Cabaretti Caterer

When Rocco, Cabaretti Caterer enters, if you cast it, you may search your library for a creature card with mana value X or less, put it onto the battlefield, then shuffle.

Kenrith, the Returned King

{R}: All creatures gain trample and haste until end of turn.
{1}{G}: Put a +1/+1 counter on target creature.
{2}{W}: Target player gains 5 life.
{3}{U}: Target player draws a card.
{4}{B}: Put target creature card from a graveyard onto the battlefield under its owner's control.

Prossh, Skyraider of Kher

When you cast this spell, create X 0/1 red Kobold creature tokens named Kobolds of Kher Keep, where X is the amount of mana spent to cast it.
Flying
Sacrifice another creature: Prossh, Skyraider of Kher gets +1/+0 until end of turn.

Atarka, World Render

Flying, trample
Whenever a Dragon you control attacks, it gains double strike until end of turn.

Kalamax, the Stormsire

Whenever you cast your first instant spell each turn, if Kalamax, the Stormsire is tapped, copy that spell. You may choose new targets for the copy.
Whenever you copy an instant spell, put a +1/+1 counter on Kalamax.

Adeline, Resplendent Cathar

Vigilance
Adeline, Resplendent Cathar's power is equal to the number of creatures you control.
Whenever you attack, for each opponent, create a 1/1 white Human creature token that's tapped and attacking that player or a planeswalker they control.

Jinnie Fay, Jetmir's Second

If you would create one or more tokens, you may instead create that many 2/2 green Cat creature tokens with haste or that many 3/1 green Dog creature tokens with vigilance.

The Prismatic Bridge

At the beginning of your upkeep, reveal cards from the top of your library until you reveal a creature or planeswalker card. Put that card onto the battlefield and the rest on the bottom of your library in a random order.

Esika, God of the Tree

Vigilance
{T}: Add one mana of any color.
Other legendary creatures you control have vigilance and "{T}: Add one mana of any color."

Esika, God of the Tree // The Prismatic Bridge

Najeela, the Blade-Blossom

Whenever a Warrior attacks, you may have its controller create a 1/1 white Warrior creature token that's tapped and attacking.
{W}{U}{B}{R}{G}: Untap all attacking creatures. They gain trample, lifelink, and haste until end of turn. After this phase, there is an additional combat phase. Activate only during combat.