Concussive Bolt

Concussive Bolt deals 4 damage to target player or planeswalker.
Metalcraft — If you control three or more artifacts, creatures controlled by that player or by that planeswalker's controller can't block this turn.

Kuldotha Rebirth

As an additional cost to cast this spell, sacrifice an artifact.
Create three 1/1 red Goblin creature tokens.

Atog

Sacrifice an artifact: Atog gets +2/+2 until end of turn.

Ingenious Artillerist

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

Scrapyard Steelbreaker

{1}, Sacrifice another artifact: Scrapyard Steelbreaker gets +2/+1 until end of turn.

Frogmite

Affinity for artifacts (This spell costs {1} less to cast for each artifact you control.)

Orcish Vandal

{T}, Sacrifice an artifact: Orcish Vandal deals 2 damage to any target.

Krark-Clan Ogre

{R}, Sacrifice an artifact: Target creature can't block this turn.

Krark-Clan Stoker

Embraal Gear-Smasher

{T}, Sacrifice an artifact: Embraal Gear-Smasher deals 2 damage to each opponent.

Toggo, Goblin Weaponsmith

Landfall — Whenever a land you control enters, create a colorless Equipment artifact token named Rock with "Equipped creature has '{1}, {T}, Sacrifice Rock: This creature deals 2 damage to any target'" and equip {1}.
Partner (You can have two commanders if both have partner.)

Salivating Gremlins

Whenever an artifact you control enters, Salivating Gremlins gets +2/+0 and gains trample until end of turn.

Artillerize

As an additional cost to cast this spell, sacrifice an artifact or creature.
Artillerize deals 5 damage to any target.

Krark-Clan Shaman

Sacrifice an artifact: Krark-Clan Shaman deals 1 damage to each creature without flying.

Battered Golem

Battered Golem doesn't untap during your untap step.
Whenever an artifact enters, you may untap Battered Golem.

Makeshift Munitions

{1}, Sacrifice an artifact or creature: Makeshift Munitions deals 1 damage to any target.

Rusted Slasher

Sacrifice an artifact: Regenerate Rusted Slasher.

Gnathosaur

Sacrifice an artifact: Gnathosaur gains trample until end of turn.

Krark-Clan Grunt

Sacrifice an artifact: Krark-Clan Grunt gets +1/+0 and gains first strike until end of turn.

Chrome Steed

Metalcraft — Chrome Steed gets +2/+2 as long as you control three or more artifacts.

Myr Enforcer

Scale of Chiss-Goria

Flash
Affinity for artifacts (This spell costs {1} less to cast for each artifact you control.)
{T}: Target creature gets +0/+1 until end of turn.

Scrapyard Mongrel

As long as you control an artifact, Scrapyard Mongrel gets +2/+0 and has trample. (It can deal excess combat damage to the player or planeswalker it's attacking.)

Penregon Strongbull

{1}, Sacrifice an artifact: Penregon Strongbull gets +1/+1 until end of turn and deals 1 damage to each opponent.

Oxidda Daredevil

Sacrifice an artifact: Oxidda Daredevil gains haste until end of turn.

Crash

You may sacrifice a Mountain rather than pay this spell's mana cost.
Destroy target artifact.