Galvanic Blast

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

Tooth of Chiss-Goria

Flash
Affinity for artifacts (This spell costs {1} less to cast for each artifact you control.)
{T}: Target creature gets +1/+0 until end of turn.

Ornithopter

Court Homunculus

Court Homunculus gets +1/+1 as long as you control another artifact.

Drossforge Bridge

Drossforge Bridge enters tapped.
Indestructible
{T}: Add {B} or {R}.

Thraben Inspector

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

Phyrexian Walker

Great Furnace

Springleaf Drum

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

Rustvale Bridge

Rustvale Bridge enters tapped.
Indestructible
{T}: Add {R} or {W}.

Fling

As an additional cost to cast this spell, sacrifice a creature.
Fling deals damage equal to the sacrificed creature's power to any target.

Temur Battle Rage

Target creature gains double strike until end of turn.
Ferocious — That creature also gains trample until end of turn if you control a creature with power 4 or greater.

Darksteel Citadel

Atog

Sacrifice an artifact: Atog gets +2/+2 until end of turn.

Frogmite

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

Vault Skirge

({B/P} can be paid with either {B} or 2 life.)
Flying
Lifelink (Damage dealt by this creature also causes you to gain that much life.)