Urza's Tower

{T}: Add {C}. If you control an Urza's Mine and an Urza's Power-Plant, add {C}{C}{C} instead.

Golem Artisan

{2}: Target artifact creature gets +1/+1 until end of turn.
{2}: Target artifact creature gains your choice of flying, trample, or haste until end of turn.

Arcane Signet

{T}: Add one mana of any color in your commander's color identity.

Shimmer Myr

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

Hovermyr

Swords to Plowshares

Exile target creature. Its controller gains life equal to its power.

Myrsmith

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

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.

Kindred Discovery

As Kindred Discovery enters, choose a creature type.
Whenever a creature you control of the chosen type enters or attacks, draw a card.

Altar of Shadows

At the beginning of your first main phase, add {B} for each charge counter on Altar of Shadows.
{7}, {T}: Destroy target creature. Then put a charge counter on Altar of Shadows.

Enlightened Tutor

Search your library for an artifact or enchantment card, reveal it, then shuffle and put that card on top.

Myr Retriever

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

Mirrodin Besieged

As Mirrodin Besieged enters, choose Mirran or Phyrexian.
• Mirran — Whenever you cast an artifact spell, create a 1/1 colorless Myr artifact creature token.
• Phyrexian — At the beginning of your end step, draw a card, then discard a card. Then if there are fifteen or more artifact cards in your graveyard, target opponent loses the game.

Doubling Cube

{3}, {T}: Double the amount of each type of unspent mana you have.

Marvin, Murderous Mimic

Marvin, Murderous Mimic has all activated abilities of creatures you control that don't have the same name as this creature.

Reliquary Tower

You have no maximum hand size.
{T}: Add {C}.

Plains

Wake the Past

Return all artifact cards from your graveyard to the battlefield. They gain haste until end of turn.

Mountain

Command Tower

Darksteel Ingot

Indestructible (Effects that say "destroy" don't destroy this artifact.)
{T}: Add one mana of any color.

Blinkmoth Urn

At the beginning of each player's first main phase, if Blinkmoth Urn is untapped, that player adds {C} for each artifact they control.

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.

Prop Room

Untap each creature you control during each other player's untap step.
(You may cast either half. That door unlocks on the battlefield. As a sorcery, you may pay the mana cost of a locked door to unlock it.)

Dazzling Theater

Creature spells you cast have convoke. (Your creatures can help cast those spells. Each creature you tap while casting a creature spell pays for {1} or one mana of that creature's color.)
(You may cast either half. That door unlocks on the battlefield. As a sorcery, you may pay the mana cost of a locked door to unlock it.)

Dazzling Theater // Prop Room

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.)

Myr Enforcer

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

Patchwork Banner

As Patchwork Banner enters, choose a creature type.
Creatures you control of the chosen type get +1/+1.
{T}: Add one mana of any color.

Myr Propagator

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

Basalt Monolith

Basalt Monolith doesn't untap during your untap step.
{T}: Add {C}{C}{C}.
{3}: Untap Basalt Monolith.

Kenrith, the Returned King

{R}: All creatures gain trample and haste until end of turn.
{1}{G}: Put a +1/+1 counter on target creature.
{2}{W}: Target player gains 5 life.
{3}{U}: Target player draws a card.
{4}{B}: Put target creature card from a graveyard onto the battlefield under its owner's control.

Lux Artillery

Whenever you cast an artifact creature spell, it gains sunburst. (It enters with a +1/+1 counter on it for each color of mana spent to cast it.)
At the beginning of your end step, if there are thirty or more counters among artifacts and creatures you control, Lux Artillery deals 10 damage to each opponent.

Counterspell

Mox Tantalite

Suspend 3—{0} (Rather than cast this card from your hand, pay {0} and exile it with three time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost.)
{T}: Add one mana of any color.

Iron Myr

Path to Exile

Exile target creature. Its controller may search their library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Darksteel Forge

Artifacts you control have indestructible. (Effects that say "destroy" don't destroy them. Artifact creatures with indestructible can't be destroyed by damage.)

Myr Sire

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

Everflowing Chalice

Multikicker {2} (You may pay an additional {2} any number of times as you cast this spell.)
Everflowing Chalice enters with a charge counter on it for each time it was kicked.
{T}: Add {C} for each charge counter on Everflowing Chalice.

Island

Thought Vessel

Urza's Mine

{T}: Add {C}. If you control an Urza's Power-Plant and an Urza's Tower, add {C}{C} instead.

Alloy Myr

Chromatic Lantern

Lands you control have "{T}: Add one mana of any color."
{T}: Add one mana of any color.

Three Tree City

As Three Tree City enters, choose a creature type.
{T}: Add {C}.
{2}, {T}: Choose a color. Add an amount of mana of that color equal to the number of creatures you control of the chosen type.

Myr Superion

Spend only mana produced by creatures to cast this spell.

Enduring Vitality

Vigilance
Creatures you control have "{T}: Add one mana of any color."
When Enduring Vitality dies, if it was a creature, return it to the battlefield under its owner's control. It's an enchantment. (It's not a creature.)

Sol Ring

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.

Lodestone Myr

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

Unwinding Clock

Untap all artifacts you control during each other player's untap step.

Tomb of the Spirit Dragon

{T}: Add {C}.
{2}, {T}: You gain 1 life for each colorless creature you control.

Darksteel Citadel

Dispatch

Tap target creature.
Metalcraft — If you control three or more artifacts, exile that creature.

Myr Galvanizer

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

Path of Ancestry

Path of Ancestry enters tapped.
{T}: Add one mana of any color in your commander's color identity. When that mana is spent to cast a creature spell that shares a creature type with your commander, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice Mind Stone: Draw a card.

Sol Talisman

Suspend 3—{1} (Rather than cast this card from your hand, pay {1} and exile it with three time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost.)
{T}: Add {C}{C}.

Silver Myr

Fellwar Stone

{T}: Add one mana of any color that a land an opponent controls could produce.

Myr Kinsmith

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

Leaden Myr

Academy Ruins

{T}: Add {C}.
{1}{U}, {T}: Put target artifact card from your graveyard on top of your library.

Frogmyr Enforcer

Prototype {3}{R} — 2/2 (You may cast this spell with different mana cost, color, and size. It keeps its abilities and types.)
Affinity for artifacts (This spell costs {1} less to cast for each artifact you control.)

Forest

Copper 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.

Commander's Sphere

{T}: Add one mana of any color in your commander's color identity.
Sacrifice Commander's Sphere: Draw a card.

Swamp

Urza's Power Plant

{T}: Add {C}. If you control an Urza's Mine and an Urza's Tower, add {C}{C} instead.

Phyrexian Arena

At the beginning of your upkeep, you draw a card and you lose 1 life.

Myr Welder

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

Helix Pinnacle

Shroud (This enchantment can't be the target of spells or abilities.)
{X}: Put X tower counters on Helix Pinnacle.
At the beginning of your upkeep, if there are 100 or more tower counters on Helix Pinnacle, you win the game.

Palladium Myr

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.

Fabricate

Search your library for an artifact card, reveal it, put it into your hand, then shuffle.

Cascading Cataracts

Indestructible
{T}: Add {C}.
{5}, {T}: Add five mana in any combination of colors.

The Millennium Calendar

Whenever you untap one or more permanents during your untap step, put that many time counters on The Millennium Calendar.
{2}, {T}: Double the number of time counters on The Millennium Calendar.
When there are 1,000 or more time counters on The Millennium Calendar, sacrifice it and each opponent loses 1,000 life.

Rhystic Study

Whenever an opponent casts a spell, you may draw a card unless that player pays {1}.

Gold Myr

Voltaic Key

Organic Extinction

Improvise (Your artifacts can help cast this spell. Each artifact you tap after you're done activating mana abilities pays for {1}.)
Destroy all nonartifact creatures.