Myr Retriever

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

Mountain

Ashnod's Altar

Silverbluff Bridge

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

Island

Myr Sire

When Myr Sire dies, create a 1/1 colorless Phyrexian Myr artifact creature token.

Valakut Invoker

{8}: Valakut Invoker deals 3 damage to any target.

Workshop Assistant

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

Thoughtcast

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

Galvanic Blast

Galvanic Blast deals 2 damage to any target.
Metalcraft — Galvanic Blast deals 4 damage instead if you control three or more artifacts.

Perilous Myr

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

Etherium Sculptor

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

Great Furnace

Spell Pierce

Counter target noncreature spell unless its controller pays {2}.

Makeshift Munitions

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

Hissing Iguanar

Whenever another creature dies, you may have Hissing Iguanar deal 1 damage to target player or planeswalker.

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.

Deep Analysis

Target player draws two cards.
Flashback—{1}{U}, Pay 3 life. (You may cast this card from your graveyard for its flashback cost. Then exile it.)