Steel Overseer

{T}: Put a +1/+1 counter on each artifact creature you control.

Seal of Cleansing

Sacrifice Seal of Cleansing: Destroy target artifact or enchantment.

Thorn of Amethyst

Noncreature spells cost {1} more to cast.

Argentum Armor

Equipped creature gets +6/+6.
Whenever equipped creature attacks, destroy target permanent.
Equip {6}

Arcbound Worker

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.)

Darksteel Citadel

Ethersworn Canonist

Each player who has cast a nonartifact spell this turn can't cast additional nonartifact spells.

Quest for the Holy Relic

Whenever you cast a creature spell, you may put a quest counter on Quest for the Holy Relic.
Remove five quest counters from Quest for the Holy Relic and sacrifice it: Search your library for an Equipment card, put it onto the battlefield, attach it to a creature you control, then shuffle.

Arcbound Mouser

Lifelink
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.)

Lupine Prototype

Lupine Prototype can't attack or block unless a player has no cards in hand.

Ornithopter

Hope of Ghirapur

Flying
Sacrifice Hope of Ghirapur: Until your next turn, target player who was dealt combat damage by Hope of Ghirapur this turn can't cast noncreature spells.

Withengar Unbound

Flying, intimidate, trample (A creature with intimidate can't be blocked except by artifact creatures and/or creatures that share a color with it.)
Whenever a player loses the game, put thirteen +1/+1 counters on Withengar Unbound.

Elbrus, the Binding Blade

Equipped creature gets +1/+0.
When equipped creature deals combat damage to a player, unattach Elbrus, the Binding Blade, then transform it.
Equip {1}

Elbrus, the Binding Blade // Withengar Unbound

Etched Champion

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

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.

Heap Doll

Sacrifice Heap Doll: Exile target card from a graveyard.

Plains

Phyrexian Revoker

As Phyrexian Revoker enters, choose a nonland card name.
Activated abilities of sources with the chosen name can't be activated.