Refurbished Familiar

Affinity for artifacts (This spell costs {1} less to cast for each artifact you control.)
Flying
When this creature enters, each opponent discards a card. For each opponent who can't, you draw a card.

Myr Enforcer

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

Utrom Monitor

Affinity for artifacts (This spell costs {1} less to cast for each artifact you control.)
Flying (This creature can't be blocked except by creatures with flying or reach.)