Metallic Rebuke

Improvise (Your artifacts can help cast this spell. Each artifact you tap after you're done activating mana abilities pays for {1}.)
Counter target spell unless its controller pays {3}.

Chromatic Star

{1}, {T}, Sacrifice this artifact: Add one mana of any color.
When this artifact is put into a graveyard from the battlefield, draw a card.

Arsenal Thresher

As this creature enters, you may reveal any number of other artifact cards from your hand. This creature enters with a +1/+1 counter on it for each card revealed this way.

Experimental Synthesizer

When this artifact enters or leaves the battlefield, exile the top card of your library. Until end of turn, you may play that card.
{2}{R}, Sacrifice this artifact: Create a 2/2 white Samurai creature token with vigilance. Activate only as a sorcery.

Golden Urn

At the beginning of your upkeep, you may put a charge counter on this artifact.
{T}, Sacrifice this artifact: You gain life equal to the number of charge counters on this artifact.

Moonsnare Prototype

{T}, Tap an untapped artifact or creature you control: Add {C}.
Channel — {4}{U}, Discard this card: The owner of target nonland permanent puts it on their choice of the top or bottom of their library.

Steel Wall

Myr Servitor

At the beginning of your upkeep, if this creature is on the battlefield, each player returns all cards named Myr Servitor from their graveyard to the battlefield.

Chromatic Sphere

{1}, {T}, Sacrifice this artifact: Add one mana of any color. Draw a card.

Navigator's Compass

When this artifact enters, you gain 3 life.
{T}: Until end of turn, target land you control becomes the basic land type of your choice in addition to its other types.