Myr Enforcer

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

Ardent Recruit

Metalcraft — Ardent Recruit gets +2/+2 as long as you control three or more artifacts.

Metalcraft — As long as you control three or more artifacts, Auriok Sunchaser gets +2/+2 and has flying.

{T}, Tap an untapped creature you control: Add one mana of any color.

{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.

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

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

This spell costs {2} less to cast if you control a Human creature and a non-Human creature.
Draw two cards.

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

Razortide Bridge enters tapped.
Indestructible
{T}: Add {W} or {U}.

Choose one —
• Counter target spell if it's blue.
• Destroy target permanent if it's blue.

Choose one —
• Counter target spell if it's red.
• Destroy target permanent if it's red.

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

Radiance — Destroy target enchantment and each other enchantment that shares a color with it.

When Thraben Inspector enters, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")