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.

Ornithopter of Paradise

Steel Overseer

{T}: Put a +1/+1 counter on each artifact creature you control.

Tempered Steel

Artifact creatures you control get +2/+2.

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.

Etherium Sculptor

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

Master of Etherium

Master of Etherium's power and toughness are each equal to the number of artifacts you control.
Other artifact creatures you control get +1/+1.

Cyberman Patrol

Artifact creatures you control have afflict 3. (Whenever a creature with afflict 3 becomes blocked, defending player loses 3 life.)