Assert Authority

Affinity for artifacts (This spell costs {1} less to cast for each artifact you control.)
Counter target spell. If that spell is countered this way, exile it instead of putting it into its owner's graveyard.

Silas Renn, Seeker Adept

Deathtouch
Whenever Silas Renn, Seeker Adept deals combat damage to a player, choose target artifact card in your graveyard. You may cast that card this turn.
Partner (You can have two commanders if both have partner.)

Rebbec, Architect of Ascension

Artifacts you control have protection from each mana value among artifacts you control.
Partner (You can have two commanders if both have partner.)

Springleaf Drum

{T}, Tap an untapped creature you control: Add one mana of any color.

Encroaching Mycosynth

Nonland permanents you control are artifacts in addition to their other types. The same is true for permanent spells you control and nonland permanent cards you own that aren't on the battlefield.

Retract

Return all artifacts you control to their owner's hand.

Myr Enforcer

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

Tormod's Crypt

{T}, Sacrifice Tormod's Crypt: Exile target player's graveyard.

Ornithopter

Frogmite

Memnite

Karmic Justice

Whenever a spell or ability an opponent controls destroys a noncreature permanent you control, you may destroy target permanent that opponent controls.

Mishra's Bauble

{T}, Sacrifice Mishra's Bauble: Look at the top card of target player's library. Draw a card at the beginning of the next turn's upkeep.

Thoughtcast

Affinity for artifacts (This spell costs {1} less to cast for each artifact you control.)
Draw two cards.

Tezzeret, Master of the Bridge

Creature and planeswalker spells you cast have affinity for artifacts. (They cost {1} less to cast for each artifact you control.)
+2: Tezzeret, Master of the Bridge deals X damage to each opponent, where X is the number of artifacts you control. You gain X life.
−3: Return target artifact card from your graveyard to your hand.
−8: Exile the top ten cards of your library. Put all artifact cards from among them onto the battlefield.