Living Brain, Mechanical Marvel

At the beginning of combat on your turn, target non-Equipment artifact you control becomes an artifact creature with base power and toughness 3/3 until end of turn. Untap it.

The Capitoline Triad

Those Who Came Before — This spell costs {1} less to cast for each historic card in your graveyard. (Artifacts, legendaries, and Sagas are historic.)
Exile any number of historic cards from your graveyard with total mana value 30 or greater: You get an emblem with "Creatures you control have base power and toughness 9/9."

Syr Ginger, the Meal Ender

Syr Ginger has trample, hexproof, and haste as long as an opponent controls a planeswalker.
Whenever another artifact you control is put into a graveyard from the battlefield, put a +1/+1 counter on Syr Ginger and scry 1.
{2}, {T}, Sacrifice Syr Ginger: You gain life equal to its power.

Krang, Utrom Warlord

Flying, trample, indestructible, haste
Other artifact creatures you control have flying, trample, indestructible, and haste.

Karn, Silver Golem

Whenever Karn blocks or becomes blocked, it gets -4/+4 until end of turn.
{1}: Target noncreature artifact becomes an artifact creature with power and toughness each equal to its mana value until end of turn.

Faceless One

If Faceless One is your commander, choose a color before the game begins. Faceless One is the chosen color.
Choose a Background (You can have a Background as a second commander.)

Karn, Legacy Reforged

Karn's power and toughness are each equal to the greatest mana value among artifacts you control.
At the beginning of your upkeep, add {C} for each artifact you control. This mana can't be spent to cast nonartifact spells. Until end of turn, you don't lose this mana as steps and phases end.

Kozilek, the Great Distortion

When you cast this spell, if you have fewer than seven cards in hand, draw cards equal to the difference.
Menace
Discard a card with mana value X: Counter target spell with mana value X.

Ultima, Origin of Oblivion

Flying
Whenever Ultima attacks, put a blight counter on target land. For as long as that land has a blight counter on it, it loses all land types and abilities and has "{T}: Add {C}."
Whenever you tap a land for {C}, add an additional {C}.

The Warring Triad

Flying, trample, haste
As long as there are fewer than eight cards in your graveyard, The Warring Triad isn't a creature.
{T}, Mill a card: Target player adds one mana of any color.

The Walls of Ba Sing Se

Defender
Other permanents you control have indestructible.

Graaz, Unstoppable Juggernaut

Juggernauts you control attack each combat if able.
Juggernauts you control can't be blocked by Walls.
Other creatures you control have base power and toughness 5/3 and are Juggernauts in addition to their other creature types.

Zhulodok, Void Gorger

Colorless spells you cast from your hand with mana value 7 or greater have "Cascade, cascade." (When you cast one, 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. Then do it again.)

ED-E, Lonesome Eyebot

Flying
ED-E My Love — Whenever you attack, if the number of attacking creatures is greater than the number of quest counters on ED-E, put a quest counter on it.
{2}, Sacrifice ED-E: Draw a card, then draw an additional card for each quest counter on ED-E.

Ulamog, the Ceaseless Hunger

When you cast this spell, exile two target permanents.
Indestructible
Whenever Ulamog attacks, defending player exiles the top twenty cards of their library.

Ulamog, the Infinite Gyre

When you cast this spell, destroy target permanent.
Indestructible
Annihilator 4 (Whenever this creature attacks, defending player sacrifices four permanents of their choice.)
When Ulamog is put into a graveyard from anywhere, its owner shuffles their graveyard into their library.

Ulamog, the Defiler

When you cast this spell, target opponent exiles the top half of their library, rounded up.
Ward—Sacrifice two permanents.
Ulamog enters with a number of +1/+1 counters on it equal to the greatest mana value among cards in exile.
Ulamog has annihilator X, where X is the number of +1/+1 counters on it.

Kozilek, Butcher of Truth

When you cast this spell, draw four cards.
Annihilator 4 (Whenever this creature attacks, defending player sacrifices four permanents of their choice.)
When Kozilek is put into a graveyard from anywhere, its owner shuffles their graveyard into their library.

Kozilek, the Broken Reality

When you cast this spell, up to two target players each manifest two cards from their hands. For each card manifested this way, you draw a card. (To manifest a card, put it onto the battlefield face down as a 2/2 creature. Turn it face up any time for its mana cost if it's a creature card.)
Other colorless creatures you control get +3/+2.

The Dawning Archaic

This spell costs {1} less to cast for each instant and sorcery card in your graveyard.
Reach
Whenever The Dawning Archaic attacks, you may cast target instant or sorcery card from your graveyard without paying its mana cost. If that spell would be put into your graveyard, exile it instead.

Iron Spider, Stark Upgrade

Vigilance
{T}: Put a +1/+1 counter on each artifact creature and/or Vehicle you control.
{2}, Remove two +1/+1 counters from among artifacts you control: Draw a card.

Dawnsire, Sunstar Dreadnought

Station (Tap another creature you control: Put charge counters equal to its power on this Spacecraft. Station only as a sorcery. It's an artifact creature at 20+.)
10+ | Whenever you attack, Dawnsire deals 100 damage to up to one target creature or planeswalker.
20+ | Flying

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.)

Liberator, Urza's Battlethopter

Flash
Flying
You may cast colorless spells and artifact spells as though they had flash.
Whenever you cast a spell, if the amount of mana spent to cast that spell is greater than Liberator's power, put a +1/+1 counter on Liberator.

Omarthis, Ghostfire Initiate

Omarthis enters with X +1/+1 counters on it.
Whenever you put one or more +1/+1 counters on another colorless creature, you may put a +1/+1 counter on Omarthis.
When Omarthis dies, manifest a number of cards from the top of your library equal to the number of counters on it.

Marvin, Murderous Mimic

Marvin has all activated abilities of creatures you control that don't have the same name as this creature.

Traxos, Scourge of Kroog

Trample
Traxos enters tapped and doesn't untap during your untap step.
Whenever you cast a historic spell, untap Traxos. (Artifacts, legendaries, and Sagas are historic.)