Cranial Plating

Equipped creature gets +1/+0 for each artifact you control.
{B}{B}: Attach Cranial Plating to target creature you control.
Equip {1}

Arcbound Ravager

Sacrifice an artifact: Put a +1/+1 counter on Arcbound Ravager.
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.)

Frogmite

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

Island

Swiftwater Cliffs

This land enters tapped.
When this land enters, you gain 1 life.
{T}: Add {U} or {R}.

Welding Jar

Sacrifice Welding Jar: Regenerate target artifact.

Galvanic Blast

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

Buried Ruin

{T}: Add {C}.
{2}, {T}, Sacrifice Buried Ruin: Return target artifact card from your graveyard to your hand.

Darksteel Citadel

Memnite

Gingerbrute

Haste (This creature can attack and {T} as soon as it comes under your control.)
{1}: Gingerbrute can't be blocked this turn except by creatures with haste.
{2}, {T}, Sacrifice Gingerbrute: You gain 3 life.

Master of Etherium

Master of Etherium's power and toughness are each equal to the number of artifacts you control.
Other artifact creatures you control get +1/+1.

Ornithopter

Springleaf Drum

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

Mountain

Kazuul's Cliffs

Kazuul's Cliffs enters tapped.
{T}: Add {R}.

Kazuul's Fury

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

Kazuul's Fury // Kazuul's Cliffs

Signal Pest

Battle cry (Whenever this creature attacks, each other attacking creature gets +1/+0 until end of turn.)
Signal Pest can't be blocked except by creatures with flying or reach.

Etched Champion

Metalcraft — Etched Champion has protection from each color as long as you control three or more artifacts.