Silver Myr

Voltaic Key

Voltaic Construct

Alloy Myr

Urza, Chief Artificer

Affinity for artifact creatures (This spell costs {1} less to cast for each artifact creature you control.)
Artifact creatures you control have menace.
At the beginning of your end step, create a 0/0 colorless Construct artifact creature token with "This token gets +1/+1 for each artifact you control."

Gold Myr

Shimmer Myr

Flash
You may cast artifact spells as though they had flash.

Leaden Myr

Sun Droplet

Whenever you're dealt damage, put that many charge counters on this artifact.
At the beginning of each upkeep, you may remove a charge counter from this artifact. If you do, you gain 1 life.

Palladium Myr

Voltaic Servant

At the beginning of your end step, untap target artifact.

Cyberman Patrol

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