Smelting Vat

{1}, {T}, Sacrifice another artifact: Reveal the top eight cards of your library. Put up to two noncreature artifact cards with total mana value less than or equal to the sacrificed artifact's mana value from among them onto the battlefield and the rest on the bottom of your library in a random order.

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.)

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice this artifact: Draw a card.

Wreck Hunter

Flash
When this creature enters, choose target player. You create a tapped Powerstone token for each nonland card in that player's graveyard that was put there from the battlefield this turn. (It's an artifact with "{T}: Add {C}. This mana can't be spent to cast a nonartifact spell.")

Ashnod the Uncaring

Deathtouch
Whenever you activate an ability of an artifact or creature that isn't a mana ability, if one or more permanents were sacrificed to activate it, you may copy that ability. You may choose new targets for the copy. (Sacrificing an artifact for mana to activate an ability doesn't count.)

Commander's Sphere

{T}: Add one mana of any color in your commander's color identity.
Sacrifice this artifact: Draw a card.