Gonti's Aether Heart

Whenever Gonti's Aether Heart or another artifact you control enters, you get {E}{E} (two energy counters).
Pay eight {E}, Exile Gonti's Aether Heart: Take an extra turn after this one.

Blinkmoth Urn

At the beginning of each player's first main phase, if Blinkmoth Urn is untapped, that player adds {C} for each artifact they control.

Mirrodin Besieged

As Mirrodin Besieged enters, choose Mirran or Phyrexian.
• Mirran — Whenever you cast an artifact spell, create a 1/1 colorless Myr artifact creature token.
• Phyrexian — At the beginning of your end step, draw a card, then discard a card. Then if there are fifteen or more artifact cards in your graveyard, target opponent loses the game.

Storage Matrix

As long as Storage Matrix is untapped, each player chooses artifact, creature, or land during their untap step. That player can untap only permanents of the chosen type this step.

Blinkmoth Infusion

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

Winter Orb

As long as Winter Orb is untapped, players can't untap more than one land during their untap steps.

Sai, Master Thopterist

Whenever you cast an artifact spell, create a 1/1 colorless Thopter artifact creature token with flying.
{1}{U}, Sacrifice two artifacts: Draw a card.

Glaring Spotlight

Creatures your opponents control with hexproof can be the targets of spells and abilities you control as though they didn't have hexproof.
{3}, Sacrifice Glaring Spotlight: Creatures you control gain hexproof until end of turn and can't be blocked this turn.

Spell Swindle

Counter target spell. Create X Treasure tokens, where X is that spell's mana value. (They're artifacts with "{T}, Sacrifice this artifact: Add one mana of any color.")