Galvanic Blast

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

Ardent Recruit

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

Vedalken Certarch

Metalcraft — {T}: Tap target artifact, creature, or land. Activate only if you control three or more artifacts.

Razortide Bridge

This land enters tapped.
Indestructible
{T}: Add {W} or {U}.

Ornithopter

Flayer Husk

Living weapon (When this Equipment enters, create a 0/0 black Phyrexian Germ creature token, then attach this to it.)
Equipped creature gets +1/+1.
Equip {2}

Springleaf Drum

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

Chrome Courier

Flying
When this creature enters, reveal the top two cards of your library. Put one of them into your hand and the other into your graveyard. If you put an artifact card into your hand this way, you gain 3 life.

Island

Plains

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.

Of One Mind

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

Sojourner's Companion

Affinity for artifacts
Artifact landcycling {2} ({2}, Discard this card: Search your library for an artifact land card, reveal it, put it into your hand, then shuffle.)

Thraben Inspector

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

Holdout Settlement

{T}: Add {C}. ({C} represents colorless mana.)
{T}, Tap an untapped creature you control: Add one mana of any color.

Auriok Sunchaser

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

Thoughtcast

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

Seat of the Synod

Ancient Den

Spell Pierce

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

Glint Hawk

Flying
When this creature enters, sacrifice it unless you return an artifact you control to its owner's hand.

Mutagenic Growth

({G/P} can be paid with either {G} or 2 life.)
Target creature gets +2/+2 until end of turn.