Urza, Prince of Kroog

Artifact creatures you control get +2/+2.
{6}: Create a token that's a copy of target artifact you control, except it's a 1/1 Soldier creature in addition to its other types.

Whir of Invention

Improvise (Your artifacts can help cast this spell. Each artifact you tap after you're done activating mana abilities pays for {1}.)
Search your library for an artifact card with mana value X or less, put it onto the battlefield, then shuffle.

Shimmer Myr

Flash
You may cast artifact spells as though they had flash.

Padeem, Consul of Innovation

Artifacts you control have hexproof. (They can't be the targets of spells or abilities your opponents control.)
At the beginning of your upkeep, if you control the artifact with the highest mana value or tied for the highest mana value, draw a card.

Dispatch

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

Vedalken Archmage

Whenever you cast an artifact spell, draw a card.

Foundry Inspector

Artifact spells you cast cost {1} less to cast.

Caltrops

Whenever a creature attacks, Caltrops deals 1 damage to it.

Myr Retriever

When Myr Retriever dies, return another target artifact card from your graveyard to your hand.

Sydri, Galvanic Genius

{U}: Target noncreature artifact becomes an artifact creature with power and toughness each equal to its mana value until end of turn.
{W}{B}: Target artifact creature gains deathtouch and lifelink until end of turn.

Sharuum the Hegemon

Flying
When Sharuum the Hegemon enters, you may return target artifact card from your graveyard to the battlefield.

Emry, Lurker of the Loch

This spell costs {1} less to cast for each artifact you control.
When Emry, Lurker of the Loch enters, mill four cards.
{T}: Choose target artifact card in your graveyard. You may cast that card this turn. (You still pay its costs. Timing rules still apply.)

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.

Swords to Plowshares

Exile target creature. Its controller gains life equal to its power.

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.

Bronze Guardian

Double strike
Ward {2} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {2}.)
Other artifacts you control have ward {2}.
Bronze Guardian's power is equal to the number of artifacts you control.

Jhoira's Familiar

Flying
Historic spells you cast cost {1} less to cast. (Artifacts, legendaries, and Sagas are historic.)

Etherium Sculptor

Baleful Strix

Flying, deathtouch
When Baleful Strix enters, draw a card.

Darksteel Forge

Artifacts you control have indestructible. (Effects that say "destroy" don't destroy them. Artifact creatures with indestructible can't be destroyed by damage.)

Voltaic Construct

Unwinding Clock

Untap all artifacts you control during each other player's untap step.

Staff of Nin

At the beginning of your upkeep, draw a card.
{T}: Staff of Nin deals 1 damage to any target.

Arcane Denial

Counter target spell. Its controller may draw up to two cards at the beginning of the next turn's upkeep.
You draw a card at the beginning of the next turn's upkeep.

Fabricate

Search your library for an artifact card, reveal it, put it into your hand, then shuffle.

Counterspell

Master Transmuter

{U}, {T}, Return an artifact you control to its owner's hand: You may put an artifact card from your hand onto the battlefield.