Sakashima of a Thousand Faces

You may have Sakashima of a Thousand Faces enter the battlefield 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.)

Moonsilver Key

{1}, {T}, Sacrifice Moonsilver Key: Search your library for an artifact card with a mana ability or a basic land card, reveal it, put it into your hand, then shuffle.

Imposter Mech

You may have Imposter Mech enter the battlefield as a copy of a creature an opponent controls, except it's a Vehicle artifact with crew 3 and it loses all other card types.
Crew 3

Liquimetal Torque

{T}: Add {C}.
{T}: Target nonland permanent becomes an artifact in addition to its other types until end of turn.

Seat of the Synod

Imprisoned in the Moon

Enchant creature, land, or planeswalker
Enchanted permanent is a colorless land with "{T}: Add {C}" and loses all other card types and abilities.

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.")

Academy Ruins

{T}: Add {C}.
{1}{U}, {T}: Put target artifact card from your graveyard on top of your library.

Talisman of Creativity

{T}: Add {C}.
{T}: Add {U} or {R}. Talisman of Creativity deals 1 damage to you.

Spire of Industry

{T}: Add {C}.
{T}, Pay 1 life: Add one mana of any color. Activate only if you control an artifact.

Skyswimmer Koi

Flying
Whenever an artifact enters the battlefield under your control, you may draw a card. If you do, discard a card.

Drossforge Bridge

Drossforge Bridge enters the battlefield tapped.
Indestructible
{T}: Add {B} or {R}.

Reckless Fireweaver

Whenever an artifact enters the battlefield under your control, Reckless Fireweaver deals 1 damage to each opponent.

Braids, Arisen Nightmare

At the beginning of your end step, you may sacrifice an artifact, creature, enchantment, land, or planeswalker. If you do, each opponent may sacrifice a permanent that shares a card type with it. For each opponent who doesn't, that player loses 2 life and you draw a card.

Thunderhawk Gunship

Flying
When Thunderhawk Gunship enters the battlefield, create two 2/2 white Astartes Warrior creature tokens with vigilance.
Whenever Thunderhawk Gunship attacks, attacking creatures you control gain flying until end of turn.
Crew 2

Tendo Ice Bridge

Tendo Ice Bridge enters the battlefield with a charge counter on it.
{T}: Add {C}.
{T}, Remove a charge counter from Tendo Ice Bridge: Add one mana of any color.

Forsaken Monument

Colorless creatures you control get +2/+2.
Whenever you tap a permanent for {C}, add an additional {C}.
Whenever you cast a colorless spell, you gain 2 life.

Bedevil

Destroy target artifact, creature, or planeswalker.

Morphic Pool

Morphic Pool enters the battlefield tapped unless you have two or more opponents.
{T}: Add {U} or {B}.

Breath of Fury

Enchant creature you control
When enchanted creature deals combat damage to a player, sacrifice it and attach Breath of Fury to a creature you control. If you do, untap all creatures you control and after this phase, there is an additional combat phase.

Reaver Titan

Void Shields — Protection from mana value 3 or less
Gatling Blaster — Whenever Reaver Titan attacks, it deals 5 damage to each opponent.
Crew 4 (Tap any number of creatures you control with total power 4 or more: This Vehicle becomes an artifact creature until end of turn.)

Chaos Warp

The owner of target permanent shuffles it into their library, then reveals the top card of their library. If it's a permanent card, they put it onto the battlefield.

Weatherlight

Flying
Whenever Weatherlight deals combat damage to a player, look at the top five cards of your library. You may reveal a historic card from among them and put it into your hand. Put the rest on the bottom of your library in a random order. (Artifacts, legendaries, and Sagas are historic.)
Crew 3

Retributive Wand

{3}, {T}: Retributive Wand deals 1 damage to any target.
When Retributive Wand is put into a graveyard from the battlefield, it deals 5 damage to any target.

Silverbluff Bridge

Silverbluff Bridge enters the battlefield tapped.
Indestructible
{T}: Add {U} or {R}.

Great Furnace

Quicksmith Genius

Whenever an artifact enters the battlefield under your control, you may discard a card. If you do, draw a card.

Thran Dynamo

Feed the Swarm

Destroy target creature or enchantment an opponent controls. You lose life equal to that permanent's mana value.

Power Depot

Power Depot enters the battlefield tapped.
{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast artifact spells or activate abilities of artifacts.
Modular 1

Mishra, Eminent One

At the beginning of combat on your turn, create a token that's a copy of target noncreature artifact you control, except its name is Mishra's Warform and it's a 4/4 Construct artifact creature in addition to its other types. It gains haste until end of turn. Sacrifice it at the beginning of the next end step.

Sol Ring

Emry, Lurker of the Loch

This spell costs {1} less to cast for each artifact you control.
When Emry, Lurker of the Loch enters the battlefield, mill four cards.
{T}: Choose target artifact card in your graveyard. You may cast that card this turn. (You still pay its costs. Timing rules still apply.)

Reckless Handling

Search your library for an artifact card, reveal it, put it into your hand, shuffle, then discard a card at random. If an artifact card was discarded this way, Reckless Handling deals 2 damage to each opponent.

Lithoform Engine

{2}, {T}: Copy target activated or triggered ability you control. You may choose new targets for the copy.
{3}, {T}: Copy target instant or sorcery spell you control. You may choose new targets for the copy.
{4}, {T}: Copy target permanent spell you control. (The copy becomes a token.)

Stormcarved Coast

Stormcarved Coast enters the battlefield tapped unless you control two or more other lands.
{T}: Add {U} or {R}.

Darksteel Citadel

Haunted Ridge

Haunted Ridge enters the battlefield tapped unless you control two or more other lands.
{T}: Add {B} or {R}.

Baleful Strix

Flying, deathtouch
When Baleful Strix enters the battlefield, draw a card.

Determined Iteration

At the beginning of combat on your turn, populate. The token created this way gains haste. Sacrifice it at the beginning of the next end step. (To populate, create a token that's a copy of a creature token you control.)

Thought Monitor

Affinity for artifacts
Flying
When Thought Monitor enters the battlefield, draw two cards.

Mountain

Shivan Reef

{T}: Add {C}.
{T}: Add {U} or {R}. Shivan Reef deals 1 damage to you.

Chromatic Orrery

You may spend mana as though it were mana of any color.
{T}: Add {C}{C}{C}{C}{C}.
{5}, {T}: Draw a card for each color among permanents you control.

Shadowblood Ridge

Executioner's Capsule

{1}{B}, {T}, Sacrifice Executioner's Capsule: Destroy target nonblack creature.

Island

Buried Ruin

{T}: Add {C}.
{2}, {T}, Sacrifice Buried Ruin: Return target artifact card from your graveyard to your hand.

Prized Statue

When Prized Statue enters the battlefield or is put into a graveyard from the battlefield, create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Shipwreck Marsh

Shipwreck Marsh enters the battlefield tapped unless you control two or more other lands.
{T}: Add {U} or {B}.

Coveted Jewel

When Coveted Jewel enters the battlefield, draw three cards.
{T}: Add three mana of any one color.
Whenever one or more creatures an opponent controls attack you and aren't blocked, that player draws three cards and gains control of Coveted Jewel. Untap it.

Servo Schematic

When Servo Schematic enters the battlefield or is put into a graveyard from the battlefield, create a 1/1 colorless Servo artifact creature token.

Combat Celebrant

If Combat Celebrant hasn't been exerted this turn, you may exert it as it attacks. When you do, untap all other creatures you control and after this phase, there is an additional combat phase. (An exerted creature won't untap during your next untap step.)

Nautiloid Ship

Flying
When Nautiloid Ship enters the battlefield, exile target player's graveyard.
Whenever Nautiloid Ship deals combat damage to a player, you may put a creature card exiled with Nautiloid Ship onto the battlefield under your control.
Crew 3

Swamp

Goblin Engineer

When Goblin Engineer enters the battlefield, you may search your library for an artifact card, put it into your graveyard, then shuffle.
{R}, {T}, Sacrifice an artifact: Return target artifact card with mana value 3 or less from your graveyard to the battlefield.

Machine God's Effigy

You may have Machine God's Effigy enter the battlefield as a copy of any creature on the battlefield, except it's an artifact and it has "{T}: Add {U}." (It's not a creature.)
{T}: Add {U}.

Commander's Sphere

{T}: Add one mana of any color in your commander's color identity.
Sacrifice Commander's Sphere: Draw a card.

Mithril Coat

Flash
Indestructible
When Mithril Coat enters the battlefield, attach it to target legendary creature you control.
Equipped creature has indestructible.
Equip {3}

Idol of Oblivion

{T}: Draw a card. Activate only if you created a token this turn.
{8}, {T}, Sacrifice Idol of Oblivion: Create a 10/10 colorless Eldrazi creature token.

Skysovereign, Consul Flagship

Flying
Whenever Skysovereign, Consul Flagship enters the battlefield or attacks, it deals 3 damage to target creature or planeswalker an opponent controls.
Crew 3 (Tap any number of creatures you control with total power 3 or more: This Vehicle becomes an artifact creature until end of turn.)

Underground River

{T}: Add {C}.
{T}: Add {U} or {B}. Underground River deals 1 damage to you.

Daretti, Scrap Savant

+2: Discard up to two cards, then draw that many cards.
−2: Sacrifice an artifact. If you do, return target artifact card from your graveyard to the battlefield.
−10: You get an emblem with "Whenever an artifact is put into your graveyard from the battlefield, return that card to the battlefield at the beginning of the next end step."
Daretti, Scrap Savant can be your commander.

Kappa Cannoneer

Improvise (Your artifacts can help cast this spell. Each artifact you tap after you're done activating mana abilities pays for {1}.)
Ward {4}
Whenever an artifact enters the battlefield under your control, put a +1/+1 counter on Kappa Cannoneer and it can't be blocked this turn.

All Is Dust

Each player sacrifices all permanents they control that are one or more colors.

Mistvault Bridge

Mistvault Bridge enters the battlefield tapped.
Indestructible
{T}: Add {U} or {B}.

Demonic Tutor

Search your library for a card, put that card into your hand, then shuffle.

Command Tower

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

Inventors' Fair

At the beginning of your upkeep, if you control three or more artifacts, you gain 1 life.
{T}: Add {C}.
{4}, {T}, Sacrifice Inventors' Fair: Search your library for an artifact card, reveal it, put it into your hand, then shuffle. Activate only if you control three or more artifacts.

Aether Hub

When Aether Hub enters the battlefield, you get {E} (an energy counter).
{T}: Add {C}.
{T}, Pay {E}: Add one mana of any color.

Thought Vessel

You have no maximum hand size.
{T}: Add {C}.

Blasphemous Act

This spell costs {1} less to cast for each creature on the battlefield.
Blasphemous Act deals 13 damage to each creature.

Irenicus's Vile Duplication

Create a token that's a copy of target creature you control, except the token has flying and it isn't legendary.

Talisman of Dominance

{T}: Add {C}.
{T}: Add {U} or {B}. Talisman of Dominance deals 1 damage to you.

The Mycosynth Gardens

{T}: Add {C}.
{1}, {T}: Add one mana of any color.
{X}, {T}: The Mycosynth Gardens becomes a copy of target nontoken artifact you control with mana value X.

The Mightstone and Weakstone

When The Mightstone and Weakstone enters the battlefield, choose one —
• Draw two cards.
• Target creature gets -5/-5 until end of turn.
{T}: Add {C}{C}. This mana can't be spent to cast nonartifact spells.
(Melds with Urza, Lord Protector.)

Talisman of Indulgence

{T}: Add {C}.
{T}: Add {B} or {R}. Talisman of Indulgence deals 1 damage to you.

Jhoira, Weatherlight Captain

Whenever you cast a historic spell, draw a card. (Artifacts, legendaries, and Sagas are historic.)

Cascade Bluffs

{T}: Add {C}.
{U/R}, {T}: Add {U}{U}, {U}{R}, or {R}{R}.

Vault of Whispers

Cursed Mirror

{T}: Add {R}.
As Cursed Mirror enters the battlefield, you may have it become a copy of any creature on the battlefield until end of turn, except it has haste.

Mana Confluence

{T}, Pay 1 life: Add one mana of any color.

Shrine of the Forsaken Gods

{T}: Add {C}.
{T}: Add {C}{C}. Spend this mana only to cast colorless spells. Activate only if you control seven or more lands.

Ashnod's Altar

Luxury Suite

Luxury Suite enters the battlefield tapped unless you have two or more opponents.
{T}: Add {B} or {R}.

Fabricate

Search your library for an artifact card, reveal it, put it into your hand, then shuffle.

Aether Spellbomb

{U}, Sacrifice Aether Spellbomb: Return target creature to its owner's hand.
{1}, Sacrifice Aether Spellbomb: Draw a card.

Bojuka Bog

Bojuka Bog enters the battlefield tapped.
When Bojuka Bog enters the battlefield, exile target player's graveyard.
{T}: Add {B}.

Sunken Ruins

{T}: Add {C}.
{U/B}, {T}: Add {U}{U}, {U}{B}, or {B}{B}.

Ichor Wellspring

When Ichor Wellspring enters the battlefield or is put into a graveyard from the battlefield, draw a card.

Sulfurous Springs

{T}: Add {C}.
{T}: Add {B} or {R}. Sulfurous Springs deals 1 damage to you.

Training Center

Training Center enters the battlefield tapped unless you have two or more opponents.
{T}: Add {U} or {R}.

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control.)
Equip {1}

Monkey Cage

When a creature enters the battlefield, sacrifice Monkey Cage and create X 2/2 green Monkey creature tokens, where X is that creature's mana value.

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice Mind Stone: Draw a card.

Krark-Clan Ironworks

Lightning Greaves

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.)
Equip {0}

Skullclamp

Equipped creature gets +1/-1.
Whenever equipped creature dies, draw two cards.
Equip {1}