Cathodion

Sol Ring

Megatog

Sacrifice an artifact: This creature gets +3/+3 and gains trample until end of turn.

Darksteel Citadel

Thran Dynamo

Myr Retriever

When this creature dies, return another target artifact card from your graveyard to your hand.

Welding Jar

Sacrifice this artifact: Regenerate target artifact.

Burnished Hart

{3}, Sacrifice this creature: Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.

Whispersilk Cloak

Equipped creature can't be blocked and has shroud. (It can't be the target of spells or abilities.)
Equip {2}

Atog

Sacrifice an artifact: This creature gets +2/+2 until end of turn.

Ornithopter

Great Furnace

Mountain

Galvanic Blast

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

Cranial Plating

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

Fireball

This spell costs {1} more to cast for each target beyond the first.
Fireball deals X damage divided evenly, rounded down, among any number of targets.

Solemn Simulacrum

When this creature enters, you may search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.
When this creature dies, you may draw a card.

Liquimetal Coating

{T}: Target permanent becomes an artifact in addition to its other types until end of turn.