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.

Negate

Myr Enforcer

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

Have

Doubling Season

If an effect would create one or more tokens under your control, it creates twice that many of those tokens instead.
If an effect would put one or more counters on a permanent you control, it puts twice that many of those counters on that permanent instead.

Iron Myr

Tainted Isle

{T}: Add {C}.
{T}: Add {U} or {B}. Activate only if you control a Swamp.

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}.

Glimmervoid

At the beginning of the end step, if you control no artifacts, sacrifice Glimmervoid.
{T}: Add one mana of any color.

Proxy

Eldrazi Monument

Creatures you control get +1/+1 and have flying and indestructible.
At the beginning of your upkeep, sacrifice a creature. If you can't, sacrifice Eldrazi Monument.

Nomad Outpost

Nomad Outpost enters tapped.
{T}: Add {R}, {W}, or {B}.

Consider

Surveil 1. (Look at the top card of your library. You may put it into your graveyard.)
Draw a card.

Mirror Entity

Changeling (This card is every creature type.)
{X}: Until end of turn, creatures you control have base power and toughness X/X and gain all creature types.

Mystic Monastery

Mystic Monastery enters tapped.
{T}: Add {U}, {R}, or {W}.

Soulstone Sanctuary

{T}: Add {C}.
{4}: This land becomes a 3/3 creature with vigilance and all creature types. It's still a land.

Mox Opal

Metalcraft — {T}: Add one mana of any color. Activate only if you control three or more artifacts.

Suntouched Myr

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

Myr Moonvessel

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control. It can attack and {T} no matter when it came under your control.)
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Leaden Myr

Vault of the Archangel

{T}: Add {C}.
{2}{W}{B}, {T}: Creatures you control gain deathtouch and lifelink until end of turn.

Throne of the High City

{T}: Add {C}.
{4}, {T}, Sacrifice Throne of the High City: You become the monarch.

Copper Myr

Arcane Sanctum

Arcane Sanctum enters tapped.
{T}: Add {W}, {U}, or {B}.

Sol Ring

Vedalken Humiliator

Metalcraft — Whenever Vedalken Humiliator attacks, if you control three or more artifacts, creatures your opponents control lose all abilities and have base power and toughness 1/1 until end of turn.

Mountain

Hovermyr

Damn

Destroy target creature. A creature destroyed this way can't be regenerated.
Overload {2}{W}{W} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Silver Myr

Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Myr Kinsmith

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

Holdout Settlement

{T}: Add {C}. ({C} represents colorless mana.)
{T}, Tap an untapped creature you control: Add one mana of any color.

Myr Superion

Spend only mana produced by creatures to cast this spell.

Myr Sire

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

Artificer Class

(Gain the next level as a sorcery to add its ability.)
The first artifact spell you cast each turn costs {1} less to cast.
{1}{U}: Level 2
When this Class becomes level 2, reveal cards from the top of your library until you reveal an artifact card. Put that card into your hand and the rest on the bottom of your library in a random order.
{5}{U}: Level 3
At the beginning of your end step, create a token that's a copy of target artifact you control.

Bojuka Bog

Bojuka Bog enters tapped.
When Bojuka Bog enters, exile target player's graveyard.
{T}: Add {B}.

Crumbling Necropolis

Crumbling Necropolis enters tapped.
{T}: Add {U}, {B}, or {R}.

Command Tower

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

The Mycosynth Gardens

{T}: Add {C}.
{1}, {T}: Add one mana of any color.
{X}, {T}: The Mycosynth Gardens becomes a copy of target nontoken artifact you control with mana value X.

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.)

Swords to Plowshares

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

Beast Within

Destroy target permanent. Its controller creates a 3/3 green Beast creature token.

Changeling Outcast

Changeling (This card is every creature type.)
Changeling Outcast can't block and can't be blocked.

Perilous Myr

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

Blasphemous Act

This spell costs {1} less to cast for each creature on the battlefield.
Blasphemous Act deals 13 damage to each creature.

Deadly Dispute

As an additional cost to cast this spell, sacrifice an artifact or creature.
Draw two cards and create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Myr Galvanizer

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

Parcel Myr

Scry 1. (Look at the top card of your library. You may put that card on the bottom.)
Draw a card.

Plains

Parasitic Implant

Enchant creature
At the beginning of your upkeep, enchanted creature's controller sacrifices it and you create a 1/1 colorless Phyrexian Myr artifact creature token.

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.)

Alloy Myr

Savage Lands

Savage Lands enters tapped.
{T}: Add {B}, {R}, or {G}.

Vedalken Archmage

Whenever you cast an artifact spell, draw a card.

Island

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.

Survivors' Encampment

{T}: Add {C}.
{T}, Tap an untapped creature you control: Add one mana of any color.

Ash Barrens

{T}: Add {C}.
Basic landcycling {1} ({1}, Discard this card: Search your library for a basic land card, reveal it, put it into your hand, 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.)

Myr Welder

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

Rampant Growth

Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Opulent Palace

Opulent Palace enters tapped.
{T}: Add {B}, {G}, or {U}.

Frontier Bivouac

Frontier Bivouac enters tapped.
{T}: Add {G}, {U}, or {R}.

Unclaimed Territory

As Unclaimed Territory enters, choose a creature type.
{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a creature spell of the chosen type.

Darksteel Citadel

Myr Scrapling

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

Seaside Citadel

Seaside Citadel enters tapped.
{T}: Add {G}, {W}, or {U}.

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.

Preordain

Scry 2, then draw a card. (To scry 2, look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.)

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.

Phyrexian Scriptures

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Put a +1/+1 counter on up to one target creature. That creature becomes an artifact in addition to its other types.
II — Destroy all nonartifact creatures.
III — Exile all opponents' graveyards.

Idol of Oblivion

{T}: Draw a card. Activate only if you created a token this turn.
{8}, {T}, Sacrifice Idol of Oblivion: Create a 10/10 colorless Eldrazi creature token.

Forest

Sandsteppe Citadel

Sandsteppe Citadel enters tapped.
{T}: Add {W}, {B}, or {G}.

Swamp

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.

Arcane Signet

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.

Kappa Cannoneer

Improvise (Your artifacts can help cast this spell. Each artifact you tap after you're done activating mana abilities pays for {1}.)
Ward {4}
Whenever Kappa Cannoneer or another artifact you control enters, put a +1/+1 counter on Kappa Cannoneer and it can't be blocked this turn.

Brudiclad, Telchor Engineer

Creature tokens you control have haste.
At the beginning of combat on your turn, create a 2/1 blue Phyrexian Myr artifact creature token. Then you may choose a token you control. If you do, each other token you control becomes a copy of that token.

Thought Monitor

Affinity for artifacts (This spell costs {1} less to cast for each artifact you control.)
Flying
When Thought Monitor enters, draw two cards.

Palladium Myr

Reanimate

Put target creature card from a graveyard onto the battlefield under your control. You lose life equal to its mana value.

Battlefield Forge

{T}: Add {C}.
{T}: Add {R} or {W}. Battlefield Forge deals 1 damage to you.

Alpha Myr

Myr Convert

Toxic 1 (Players dealt combat damage by this creature also get a poison counter.)
{T}, Pay 2 life: Add one mana of any color.

Command Beacon

{T}: Add {C}.
{T}, Sacrifice Command Beacon: Put your commander into your hand from the command zone.

Gold Myr

Toski, Bearer of Secrets

This spell can't be countered.
Indestructible
Toski, Bearer of Secrets attacks each combat if able.
Whenever a creature you control deals combat damage to a player, draw a card.

Exotic Orchard

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