Workshop Assistant

When Workshop Assistant dies, return another target artifact card from your graveyard to your hand.

Encrust

Enchant artifact or creature
Enchanted permanent doesn't untap during its controller's untap step and its activated abilities can't be activated.

Ulamog's Crusher

Annihilator 2 (Whenever this creature attacks, defending player sacrifices two permanents.)
Ulamog's Crusher attacks each combat if able.

Urza's Power Plant

{T}: Add {C}. If you control an Urza's Mine and an Urza's Tower, add {C}{C} instead.

Disciple of the Vault

Whenever an artifact is put into a graveyard from the battlefield, you may have target opponent lose 1 life.

Frogmite

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

Artificer's Assistant

Flying
Whenever you cast a historic spell, scry 1. (Artifacts, legendaries, and Sagas are historic. To scry 1, look at the top card of your library, then you may put that card on the bottom of your library.)

Swamp

Urza's Tower

{T}: Add {C}. If you control an Urza's Mine and an Urza's Power-Plant, add {C}{C}{C} instead.

Gearseeker Serpent

This spell costs {1} less to cast for each artifact you control.
{5}{U}: Gearseeker Serpent can't be blocked this turn.

Powerstone Shard

{T}: Add {C} for each artifact you control named Powerstone Shard.

Island

Metallic Rebuke

Improvise (Your artifacts can help cast this spell. Each artifact you tap after you're done activating mana abilities pays for {1}.)
Counter target spell unless its controller pays {3}.

Urza's Mine

{T}: Add {C}. If you control an Urza's Power-Plant and an Urza's Tower, add {C}{C} instead.

Etherium Sculptor

Artifact spells you cast cost {1} less to cast.

Cabal Paladin

Whenever you cast a historic spell, Cabal Paladin deals 2 damage to each opponent. (Artifacts, legendaries, and Sagas are historic.)