Workshop Assistant

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

Spire Golem

Affinity for Islands (This spell costs {1} less to cast for each Island you control.)
Flying

Ashnod's Altar

Reverse Engineer

Improvise (Your artifacts can help cast this spell. Each artifact you tap after you're done activating mana abilities pays for {1}.)
Draw three cards.

Etherium Sculptor

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

Parcel Myr

Chromatic Star

{1}, {T}, Sacrifice Chromatic Star: Add one mana of any color.
When Chromatic Star is put into a graveyard from the battlefield, draw a card.

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}.

Island

Mnemonic Sphere

{1}{U}, Sacrifice Mnemonic Sphere: Draw two cards.
Channel — {U}, Discard Mnemonic Sphere: Draw a card.

Seat of the Synod

Golem Foundry

Whenever you cast an artifact spell, you may put a charge counter on Golem Foundry.
Remove three charge counters from Golem Foundry: Create a 3/3 colorless Golem artifact creature token.

Thoughtcast

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

Perilous Myr

When Perilous Myr dies, it deals 2 damage to any target.

Myr Retriever

When Myr Retriever dies, return another target artifact card from your graveyard to your hand.