Heirloom Blade

Equipped creature gets +3/+1.
Whenever equipped creature dies, you may reveal cards from the top of your library until you reveal a creature card that shares a creature type with it. Put that card into your hand and the rest on the bottom of your library in a random order.
Equip {1}

Knighted Myr

{2}{W}: Adapt 1. (If this creature has no +1/+1 counters on it, put a +1/+1 counter on it.)
Whenever one or more +1/+1 counters are put on Knighted Myr, it gains double strike until end of turn.

Myr Incubator

{6}, {T}, Sacrifice Myr Incubator: Search your library for any number of artifact cards, exile them, then create that many 1/1 colorless Myr artifact creature tokens. Then shuffle.

Myr Welder

Imprint — {T}: Exile target artifact card from a graveyard.
Myr Welder has all activated abilities of all cards exiled with it.

Myr Mindservant

Tempered Steel

Artifact creatures you control get +2/+2.

Grafted Exoskeleton

Equipped creature gets +2/+2 and has infect. (It deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
Whenever Grafted Exoskeleton becomes unattached from a permanent, sacrifice that permanent.
Equip {2}

Radiant Destiny

Ascend (If you control ten or more permanents, you get the city's blessing for the rest of the game.)
As Radiant Destiny enters, choose a creature type.
Creatures you control of the chosen type get +1/+1. As long as you have the city's blessing, they also have vigilance.

Myr Battlesphere

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

Deathrender

Equipped creature gets +2/+2.
Whenever equipped creature dies, you may put a creature card from your hand onto the battlefield and attach Deathrender to it.
Equip {2}

Forebear's Blade

Equipped creature gets +3/+0 and has vigilance and trample.
Whenever equipped creature dies, attach Forebear's Blade to target creature you control.
Equip {3}

Myr Scrapling

Sacrifice Myr Scrapling: Put a +1/+1 counter on target creature.

Genesis Chamber

Whenever a nontoken creature enters, if Genesis Chamber is untapped, that creature's controller creates a 1/1 colorless Myr artifact creature token.

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.

Wings of Hubris

Equipped creature has flying.
Sacrifice Wings of Hubris: Equipped creature can't be blocked this turn. Sacrifice it at the beginning of the next end step.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Iron Myr

Stoneforge Masterwork

Equipped creature gets +1/+1 for each other creature you control that shares a creature type with it.
Equip {2}

Obelisk of Urd

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
As Obelisk of Urd enters, choose a creature type.
Creatures you control of the chosen type get +2/+2.

Sylvok Lifestaff

Equipped creature gets +1/+0.
Whenever equipped creature dies, you gain 3 life.
Equip {1}

Nettlecyst

Living weapon (When this Equipment enters, create a 0/0 black Phyrexian Germ creature token, then attach this to it.)
Equipped creature gets +1/+1 for each artifact and/or enchantment you control.
Equip {2}

Myr Moonvessel

Myr Reservoir

{T}: Add {C}{C}. Spend this mana only to cast Myr spells or activate abilities of Myr.
{3}, {T}: Return target Myr card from your graveyard to your hand.

Mishra's Workshop

{T}: Add {C}{C}{C}. Spend this mana only to cast artifact spells.

Inventors' Fair

At the beginning of your upkeep, if you control three or more artifacts, you gain 1 life.
{T}: Add {C}.
{4}, {T}, Sacrifice Inventors' Fair: Search your library for an artifact card, reveal it, put it into your hand, then shuffle. Activate only if you control three or more artifacts.

Spire of Industry

{T}: Add {C}.
{T}, Pay 1 life: Add one mana of any color. Activate only if you control an artifact.

Alpha Myr

Coretapper

{T}: Put a charge counter on target artifact.
Sacrifice Coretapper: Put two charge counters on target artifact.

Myr Prototype

At the beginning of your upkeep, put a +1/+1 counter on Myr Prototype.
Myr Prototype can't attack or block unless you pay {1} for each +1/+1 counter on it.

Plains

Myr Adapter

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

Myr Turbine

{T}: Create a 1/1 colorless Myr artifact creature token.
{T}, Tap five untapped Myr you control: Search your library for a Myr creature card, put it onto the battlefield, then shuffle.

Lodestone Myr

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

Darksteel Myr

Indestructible (Damage and effects that say "destroy" don't destroy this creature. If its toughness is 0 or less, it's still put into its owner's graveyard.)

Mountain

Myr Retriever

When Myr Retriever dies, return another target artifact card from your graveyard to your hand.

Bloodline Pretender

Changeling (This card is every creature type.)
As Bloodline Pretender enters, choose a creature type.
Whenever another creature you control of the chosen type enters, put a +1/+1 counter on Bloodline Pretender.

Brass Squire

{T}: Attach target Equipment you control to target creature you control.

Myr Sire

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

Myr Quadropod

{3}: Switch Myr Quadropod's power and toughness until end of turn.

Myr Superion

Spend only mana produced by creatures to cast this spell.

Icon of Ancestry

As Icon of Ancestry enters, choose a creature type.
Creatures you control of the chosen type get +1/+1.
{3}, {T}: Look at the top three cards of your library. You may reveal a creature card of the chosen type from among them and put it into your hand. Put the rest on the bottom of your library in a random order.

Myr Matrix

Indestructible (Effects that say "destroy" don't destroy this artifact.)
Myr creatures get +1/+1.
{5}: Create a 1/1 colorless Myr artifact creature token.

Thirsting Axe

Equipped creature gets +4/+0.
At the beginning of your end step, if equipped creature didn't deal combat damage to a creature this turn, sacrifice it.
Equip {2}

Gold Myr

Myr Propagator

{3}, {T}: Create a token that's a copy of Myr Propagator.

Myr Galvanizer

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

Banshee's Blade

Equipped creature gets +1/+1 for each charge counter on Banshee's Blade.
Whenever equipped creature deals combat damage, put a charge counter on Banshee's Blade.
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery. This card enters unattached and stays on the battlefield if the creature leaves.)

Myr Landshaper

{T}: Target land becomes an artifact in addition to its other types until end of turn.

Shimmer Myr

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

Rally the Ranks

As Rally the Ranks enters, choose a creature type.
Creatures you control of the chosen type get +1/+1.

Chief of the Foundry

Other artifact creatures you control get +1/+1.

Origin Spellbomb

{1}, {T}, Sacrifice Origin Spellbomb: Create a 1/1 colorless Myr artifact creature token.
When Origin Spellbomb is put into a graveyard from the battlefield, you may pay {W}. If you do, draw a card.

Plague Myr

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
{T}: Add {C}.

Hovermyr

Palladium Myr

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.

Shrine of Loyal Legions

At the beginning of your upkeep and whenever you cast a white spell, put a charge counter on Shrine of Loyal Legions.
{3}, {T}, Sacrifice Shrine of Loyal Legions: Create a 1/1 colorless Phyrexian Myr artifact creature token for each charge counter on Shrine of Loyal Legions.

Myr Enforcer

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

Brass Herald

As Brass Herald enters, choose a creature type.
When Brass Herald enters, reveal the top four cards of your library. Put all creature cards of the chosen type revealed this way into your hand and the rest on the bottom of your library in any order.
Creatures of the chosen type get +1/+1.

Demonmail Hauberk

Equipped creature gets +4/+2.
Equip—Sacrifice a creature.

Suntouched Myr

Sunburst (This enters with a +1/+1 counter on it for each color of mana spent to cast it.)

Losheel, Clockwork Scholar

Prevent all combat damage that would be dealt to attacking artifact creatures you control.
Whenever one or more artifact creatures you control enter, draw a card. This ability triggers only once each turn.

Urza's Incubator

As Urza's Incubator enters, choose a creature type.
Creature spells of the chosen type cost {2} less to cast.

Adaptive Automaton

As this creature enters, choose a creature type.
This creature is the chosen type in addition to its other types.
Other creatures you control of the chosen type get +1/+1.

Alibou, Ancient Witness

Other artifact creatures you control have haste.
Whenever one or more artifact creatures you control attack, Alibou, Ancient Witness deals X damage to any target and you scry X, where X is the number of tapped artifacts you control.

Phyrexia's Core

{T}: Add {C}.
{1}, {T}, Sacrifice an artifact: You gain 1 life.

Grafted Wargear

Equipped creature gets +3/+2.
Whenever Grafted Wargear becomes unattached from a permanent, sacrifice that permanent.
Equip {0} ({0}: Attach to target creature you control. Equip only as a sorcery.)

Buried Ruin

{T}: Add {C}.
{2}, {T}, Sacrifice Buried Ruin: Return target artifact card from your graveyard to your hand.

Myrsmith

Whenever you cast an artifact spell, you may pay {1}. If you do, create a 1/1 colorless Myr artifact creature token.

Herald's Horn

As Herald's Horn enters, choose a creature type.
Creature spells you cast of the chosen type cost {1} less to cast.
At the beginning of your upkeep, look at the top card of your library. If it's a creature card of the chosen type, you may reveal it and put it into your hand.

Perilous Myr

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

Omega Myr

Armory of Iroas

Whenever equipped creature attacks, put a +1/+1 counter on it.
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)