Myr Sire

When Myr Sire dies, create a 1/1 colorless Phyrexian Myr artifact creature token.

Seat of the Synod

Great Furnace

Ichorclaw Myr

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
Whenever Ichorclaw Myr becomes blocked, it gets +2/+2 until end of turn.

Hovermyr

Tree of Tales

Myr Servitor

At the beginning of your upkeep, if Myr Servitor is on the battlefield, each player returns all cards named Myr Servitor from their graveyard to the battlefield.

Darksteel Citadel

Perilous Myr

When Perilous Myr dies, it deals 2 damage to any target.

Counterspell

Welding Jar

Sacrifice Welding Jar: Regenerate target artifact.

Distant Melody

Choose a creature type. Draw a card for each permanent you control of that type.

Horned Helm

Equipped creature gets +1/+1 and has trample.
{G}{G}: Attach Horned Helm to target creature you control.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Vault of Whispers

Myr Adapter

Myr Adapter gets +1/+1 for each Equipment attached to it.

Whispersilk Cloak

Equipped creature can't be blocked and has shroud. (It can't be the target of spells or abilities.)
Equip {2}

Journey to Nowhere

When Journey to Nowhere enters, exile target creature.
When Journey to Nowhere leaves the battlefield, return the exiled card to the battlefield under its owner's control.

Vulshok Morningstar

Equipped creature gets +2/+2.
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

Myr Enforcer

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

Bonesplitter

Bone Saw

Equipped creature gets +1/+0.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Leonin Scimitar

Equipped creature gets +1/+1.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Galvanic Blast

Galvanic Blast deals 2 damage to any target.
Metalcraft — Galvanic Blast deals 4 damage instead if you control three or more artifacts.

Refurbished Familiar

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

Rancor

Enchant creature
Enchanted creature gets +2/+0 and has trample.
When Rancor is put into a graveyard from the battlefield, return Rancor to its owner's hand.