Copper Myr

Myr Kinsmith

When this creature enters, you may search your library for a Myr card, reveal it, put it into your hand, then shuffle.

Leaden Myr

Gold Myr

Urtet, Remnant of Memnarch

Whenever you cast a Myr spell, create a 1/1 colorless Myr artifact creature token.
At the beginning of combat on your turn, untap each Myr you control.
{W}{U}{B}{R}{G}, {T}: Put three +1/+1 counters on each Myr you control. Activate only during your turn.

Hovermyr

Myr Battlesphere

When this creature enters, create four 1/1 colorless Myr artifact creature tokens.
Whenever this creature attacks, you may tap X untapped Myr you control. If you do, this creature gets +X/+0 until end of turn and deals X damage to the player or planeswalker it's attacking.

Myr Enforcer

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

Lodestone Myr

Trample
Tap an untapped artifact you control: This creature gets +1/+1 until end of turn.

Myr Galvanizer

Other Myr creatures you control get +1/+1.
{1}, {T}: Untap each other Myr you control.