Gold Myr

Foundry Inspector

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

Tree of Tales

Gearseeker Serpent

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

Frogmite

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

Great Furnace

Vault of Whispers

Porcelain Legionnaire

({W/P} can be paid with either {W} or 2 life.)
First strike

Myr Enforcer

Darksteel Citadel

Mountain

Etherium Sculptor

Phyrexian Hulk

Ancient Den

Glassdust Hulk

Whenever another artifact you control enters, Glassdust Hulk gets +1/+1 until end of turn and can't be blocked this turn.
Cycling {W/U} ({W/U}, Discard this card: Draw a card.)

Arcbound Prototype

Modular 2 (This creature enters with two +1/+1 counters on it. When it dies, you may put its +1/+1 counters on target artifact creature.)

Ethersworn Shieldmage

Flash
When Ethersworn Shieldmage enters, prevent all damage that would be dealt to artifact creatures this turn.

Filigree Crawler

When Filigree Crawler dies, create a 1/1 colorless Thopter artifact creature token with flying.

Goldhound

First strike
Menace (This creature can't be blocked except by two or more creatures.)
{T}, Sacrifice Goldhound: Add one mana of any color.

Island

Ichor Wellspring

When Ichor Wellspring enters or is put into a graveyard from the battlefield, draw a card.

Primal Clay

As Primal Clay enters, it becomes your choice of a 3/3 artifact creature, a 2/2 artifact creature with flying, or a 1/6 Wall artifact creature with defender in addition to its other types. (A creature with defender can't attack.)

Pierce Strider

When Pierce Strider enters, target opponent loses 3 life.

Arcbound Worker

Modular 1 (This creature enters with a +1/+1 counter on it. When it dies, you may put its +1/+1 counters on target artifact creature.)

Deadly Dispute

As an additional cost to cast this spell, sacrifice an artifact or creature.
Draw two cards and create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")