Foundry Inspector

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

Prophetic Prism

When this artifact enters, draw a card.
{1}, {T}: Add one mana of any color.

Emry, Lurker of the Loch

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

Harnfel, Horn of Bounty

Discard a card: Exile the top two cards of your library. You may play those cards this turn.

Birgi, God of Storytelling

Whenever you cast a spell, add {R}. Until end of turn, you don't lose this mana as steps and phases end.
Creatures you control can boast twice during each of your turns rather than once.

Birgi, God of Storytelling // Harnfel, Horn of Bounty

Alchemist's Vial

When this artifact enters, draw a card.
{1}, {T}, Sacrifice this artifact: Target creature can't attack or block this turn.

Island

Mox Amber

{T}: Add one mana of any color among legendary creatures and planeswalkers you control.

Paradoxical Outcome

Return any number of target nonland, nontoken permanents you control to their owners' hands. Draw a card for each card returned to your hand this way.

Ornithopter

Golden Egg

When this artifact enters, draw a card.
{1}, {T}, Sacrifice this artifact: Add one mana of any color.
{2}, {T}, Sacrifice this artifact: You gain 3 life.

Terrarion

This artifact enters tapped.
{2}, {T}, Sacrifice this artifact: Add two mana in any combination of colors.
When this artifact is put into a graveyard from the battlefield, draw a card.

Inspiring Statuary

Nonartifact spells you cast have improvise. (Your artifacts can help cast those spells. Each artifact you tap after you're done activating mana abilities pays for {1}.)