Metallic Rebuke

Improvise (Your artifacts can help cast this spell. Each artifact you tap after you're done activating mana abilities pays for {1}.)
Counter target spell unless its controller pays {3}.

Galvanic Blast

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

Spirebluff Canal

Spirebluff Canal enters tapped unless you control two or fewer other lands.
{T}: Add {U} or {R}.

Ghostfire Blade

Equipped creature gets +2/+2.
Equip {3}
Ghostfire Blade's equip ability costs {2} less to activate if it targets a colorless creature.

Spell Pierce

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

Skilled Animator

When Skilled Animator enters, target artifact you control becomes an artifact creature with base power and toughness 5/5 for as long as Skilled Animator remains on the battlefield.

Shrapnel Blast

As an additional cost to cast this spell, sacrifice an artifact.
Shrapnel Blast deals 5 damage to any target.

Island

Scalding Tarn

{T}, Pay 1 life, Sacrifice Scalding Tarn: Search your library for an Island or Mountain card, put it onto the battlefield, then shuffle.

Darksteel Citadel

Memnite

Ornithopter

Ensoul Artifact

Enchant artifact
Enchanted artifact is a creature with base power and toughness 5/5 in addition to its other types.

Steam Vents

({T}: Add {U} or {R}.)
As Steam Vents enters, you may pay 2 life. If you don't, it enters tapped.

Springleaf Drum

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

Mountain

Darksteel Relic

Indestructible (Effects that say "destroy" don't destroy this artifact.)

Bring to Life

Target noncreature artifact you control becomes a 0/0 artifact creature. Put four +1/+1 counters on it.