Myr Enforcer

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

Dismember

({B/P} can be paid with either {B} or 2 life.)
Target creature gets -5/-5 until end of turn.

Thought Monitor

Affinity for artifacts (This spell costs {1} less to cast for each artifact you control.)
Flying
When this creature enters, draw two cards.

Nettlecyst

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 for each artifact and/or enchantment you control.
Equip {2}

Mistvault Bridge

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

Soul-Guide Lantern

When this artifact enters, exile target card from a graveyard.
{T}, Sacrifice this artifact: Exile each opponent's graveyard.
{1}, {T}, Sacrifice this artifact: Draw a card.

Shadowspear

Equipped creature gets +1/+1 and has trample and lifelink.
{1}: Permanents your opponents control lose hexproof and indestructible until end of turn.
Equip {2}

Springleaf Drum

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

Vapor Snag

Return target creature to its owner's hand. Its controller loses 1 life.

Dispatch

Tap target creature.
Metalcraft — If you control three or more artifacts, exile that creature.

Urza's Saga

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — This Saga gains "{T}: Add {C}."
II — This Saga gains "{2}, {T}: Create a 0/0 colorless Construct artifact creature token with 'This token gets +1/+1 for each artifact you control.'"
III — Search your library for an artifact card with mana cost {0} or {1}, put it onto the battlefield, then shuffle.

Ornithopter

Spire of Industry

{T}: Add {C}.
{T}, Pay 1 life: Add one mana of any color. Activate only if you control an artifact.

Memnite

Treasure Vault

{T}: Add {C}.
{X}{X}, {T}, Sacrifice this land: Create X Treasure tokens.

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.)

Simulacrum Synthesizer

When this artifact enters, scry 2.
Whenever another artifact you control with mana value 3 or greater enters, create a 0/0 colorless Construct artifact creature token with "This token gets +1/+1 for each artifact you control."

Darksteel Citadel

Tormod's Crypt

{T}, Sacrifice this artifact: Exile target player's graveyard.

Etched Champion

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

Welding Jar

Sacrifice this artifact: Regenerate target artifact.

Cranial Plating

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

Frogmite

Soulless Jailer

Permanent cards in graveyards can't enter the battlefield.
Players can't cast noncreature spells from graveyards or exile.

Thoughtcast

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