Sword of Hours

Whenever equipped creature attacks, put a +1/+1 counter on it.
Whenever equipped creature deals combat damage, roll a d12. If the result is greater than the damage dealt or the result is 12, double the number of +1/+1 counters on that creature.
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

Organic Extinction

Improvise (Your artifacts can help cast this spell. Each artifact you tap after you're done activating mana abilities pays for {1}.)
Destroy all nonartifact creatures.

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.

Sentinel Sarah Lyons

Haste
As long as an artifact entered the battlefield under your control this turn, creatures you control get +2/+2.
Battalion — Whenever Sentinel Sarah Lyons and at least two other creatures attack, Sentinel Sarah Lyons deals damage equal to the number of artifacts you control to target player.

Tear

Destroy target enchantment.
Fuse (You may cast one or both halves of this card from your hand.)

Wear

Destroy target artifact.
Fuse (You may cast one or both halves of this card from your hand.)

Wear // Tear

Hour of Reckoning

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
Destroy all nontoken creatures.

Andúril, Narsil Reforged

Ascend (If you control ten or more permanents, you get the city's blessing for the rest of the game.)
Whenever equipped creature attacks, put a +1/+1 counter on each creature you control. If you have the city's blessing, put two +1/+1 counters on each creature you control instead.
Equip {3}

Alibou, Ancient Witness

Other artifact creatures you control have haste.
Whenever one or more artifact creatures you control attack, Alibou, Ancient Witness deals X damage to any target and you scry X, where X is the number of tapped artifacts you control.

Unbreakable Formation

Creatures you control gain indestructible until end of turn.
Addendum — If you cast this spell during your main phase, put a +1/+1 counter on each of those creatures and they gain vigilance until end of turn.

Purphoros, God of the Forge

Indestructible
As long as your devotion to red is less than five, Purphoros isn't a creature.
Whenever another creature you control enters, Purphoros deals 2 damage to each opponent.
{2}{R}: Creatures you control get +1/+0 until end of turn.

Tempered Steel

Artifact creatures you control get +2/+2.

Mondrak, Glory Dominus

If one or more tokens would be created under your control, twice that many of those tokens are created instead.
{1}{W/P}{W/P}, Sacrifice two other artifacts and/or creatures: Put an indestructible counter on Mondrak, Glory Dominus. ({W/P} can be paid with either {W} or 2 life.)

Threefold Thunderhulk

Threefold Thunderhulk enters with three +1/+1 counters on it.
Whenever Threefold Thunderhulk enters or attacks, create a number of 1/1 colorless Gnome artifact creature tokens equal to its power.
{2}, Sacrifice another artifact: Put a +1/+1 counter on Threefold Thunderhulk.

Arcane Signet

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

Barracks of the Thousand

(Transforms from Thousand Moons Smithy.)
{T}: Add {W}.
Whenever you cast an artifact or creature spell using mana produced by Barracks of the Thousand, create a white Gnome Soldier artifact creature token with "This creature's power and toughness are each equal to the number of artifacts and/or creatures you control."

Thousand Moons Smithy

When Thousand Moons Smithy enters, create a white Gnome Soldier artifact creature token with "This creature's power and toughness are each equal to the number of artifacts and/or creatures you control."
At the beginning of your first main phase, you may tap five untapped artifacts and/or creatures you control. If you do, transform Thousand Moons Smithy.

Thousand Moons Smithy // Barracks of the Thousand

Darksteel Forge

Artifacts you control have indestructible. (Effects that say "destroy" don't destroy them. Artifact creatures with indestructible can't be destroyed by damage.)

Loyal Apprentice

Haste
Lieutenant — At the beginning of combat on your turn, if you control your commander, create a 1/1 colorless Thopter artifact creature token with flying. That token gains haste until end of turn.

Devilish Valet

Trample, haste
Alliance — Whenever another creature you control enters, double Devilish Valet's power until end of turn.

Steel Overseer

{T}: Put a +1/+1 counter on each artifact creature you control.

Extruder

Echo {4} (At the beginning of your upkeep, if this came under your control since the beginning of your last upkeep, sacrifice it unless you pay its echo cost.)
Sacrifice an artifact: Put a +1/+1 counter on target creature.

Krenko, Tin Street Kingpin

Whenever Krenko, Tin Street Kingpin attacks, put a +1/+1 counter on it, then create a number of 1/1 red Goblin creature tokens equal to Krenko's power.

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.

Luminarch Aspirant

At the beginning of combat on your turn, put a +1/+1 counter on target creature you control.

Warleader's Call

Creatures you control get +1/+1.
Whenever a creature you control enters, Warleader's Call deals 1 damage to each opponent.

Dispatch

Tap target creature.
Metalcraft — If you control three or more artifacts, exile that creature.

Halo Fountain

{W}, {T}, Untap a tapped creature you control: Create a 1/1 green and white Citizen creature token.
{W}{W}, {T}, Untap two tapped creatures you control: Draw a card.
{W}{W}{W}{W}{W}, {T}, Untap fifteen tapped creatures you control: You win the game.

Darksteel Mutation

Enchant creature
Enchanted creature is an Insect artifact creature with base power and toughness 0/1 and has indestructible, and it loses all other abilities, card types, and creature types.

General Ferrous Rokiric

Hexproof from monocolored
Whenever you cast a multicolored spell, create a 4/4 red and white Golem artifact creature token.

Ingenious Artillerist

Whenever one or more artifacts you control enter, Ingenious Artillerist deals that much damage to each opponent.