Maskwood Nexus

Creatures you control are every creature type. The same is true for creature spells you control and creature cards you own that aren't on the battlefield.
{3}, {T}: Create a 2/2 blue Shapeshifter creature token with changeling. (It is every creature type.)

Myr Sire

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

Scrubland

Underground Sea

Arid Mesa

{T}, Pay 1 life, Sacrifice this land: Search your library for a Mountain or Plains card, put it onto the battlefield, then shuffle.

Phyrexian Altar

Sacrifice a creature: Add one mana of any color.

Bloodstained Mire

{T}, Pay 1 life, Sacrifice this land: Search your library for a Swamp or Mountain card, put it onto the battlefield, then shuffle.

Swamp

Herald's Horn

As this artifact 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.

Door of Destinies

As this artifact enters, choose a creature type.
Whenever you cast a spell of the chosen type, put a charge counter on this artifact.
Creatures you control of the chosen type get +1/+1 for each charge counter on this artifact.

Scalding Tarn

{T}, Pay 1 life, Sacrifice this land: Search your library for an Island or Mountain card, put it onto the battlefield, then shuffle.

Goblin Bombardment

Sacrifice a creature: This enchantment deals 1 damage to any target.

Urza, Lord High Artificer

When Urza enters, create a 0/0 colorless Construct artifact creature token with "This token gets +1/+1 for each artifact you control."
Tap an untapped artifact you control: Add {U}.
{5}: Shuffle your library, then exile the top card. Until end of turn, you may play that card without paying its mana cost.

Ingenious Artillerist

Whenever one or more artifacts you control enter, this creature deals that much damage to each opponent.

Commander's Sphere

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

Bayou

Sarcomite Myr

{2}: This creature gains flying until end of turn.
{2}, Sacrifice this creature: Draw a card.

Phyrexian Metamorph

({U/P} can be paid with either {U} or 2 life.)
You may have this creature enter as a copy of any artifact or creature on the battlefield, except it's an artifact in addition to its other types.

Perilous Myr

When this creature dies, it deals 2 damage to any target.

Volcanic Island

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 this creature becomes blocked, it gets +2/+2 until end of turn.

Windswept Heath

{T}, Pay 1 life, Sacrifice this land: Search your library for a Forest or Plains card, put it onto the battlefield, then shuffle.

Alloy Myr

Diabolic Intent

As an additional cost to cast this spell, sacrifice a creature.
Search your library for a card, put that card into your hand, then shuffle.

Palladium Myr

Badlands

Myr Propagator

{3}, {T}: Create a token that's a copy of this creature.

Myr Moonvessel

Plains

Kindred Dominance

Choose a creature type. Destroy all creatures that aren't of the chosen type.

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 this artifact.

Radiant Destiny

Ascend (If you control ten or more permanents, you get the city's blessing for the rest of the game.)
As this enchantment 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.

Halimar Excavator

Whenever this creature or another Ally you control enters, target player mills X cards, where X is the number of Allies you control.

Myrsmith

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

Scrap Trawler

Whenever this creature dies or another artifact you control is put into a graveyard from the battlefield, return to your hand target artifact card in your graveyard with lesser mana value.

Hovermyr

Brass Herald

As this creature enters, choose a creature type.
When this creature 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.

Gold Myr

Turntimber Ranger

Whenever this creature or another Ally you control enters, you may create a 2/2 green Wolf creature token. If you do, put a +1/+1 counter on this creature.

Tropical Island

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}.

Savannah

Sol Ring

Silver Myr

Anointed Procession

If an effect would create one or more tokens under your control, it creates twice that many of those tokens instead.

Mirrorworks

Whenever another nontoken artifact you control enters, you may pay {2}. If you do, create a token that's a copy of that artifact.

Reckless Fireweaver

Whenever an artifact you control enters, this creature deals 1 damage to each opponent.

Flameshadow Conjuring

Whenever a nontoken creature you control enters, you may pay {R}. If you do, create a token that's a copy of that creature. That token gains haste. Exile it at the beginning of the next end step.

Plateau

Conspiracy

As this enchantment enters, choose a creature type.
Creatures you control are the chosen type. The same is true for creature spells you control and creature cards you own that aren't on the battlefield.

Chromatic Lantern

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

Taiga

Purphoros, God of the Forge

Indestructible
As long as your devotion to red is less than five, Purphoros isn't a creature.
Whenever another creature you control enters, Purphoros deals 2 damage to each opponent.
{2}{R}: Creatures you control get +1/+0 until end of turn.

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.

Tundra

Arcane Signet

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

Darksteel Myr

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

Demonic Tutor

Search your library for a card, put that card into your hand, then shuffle.

Timeless Lotus

Timeless Lotus enters tapped.
{T}: Add {W}{U}{B}{R}{G}.

Copper Myr

Forest

Wooded Foothills

{T}, Pay 1 life, Sacrifice this land: Search your library for a Mountain or Forest card, put it onto the battlefield, then shuffle.

Impact Tremors

Whenever a creature you control enters, this enchantment deals 1 damage to each opponent.

Parcel Myr

{2}, Sacrifice this creature: Draw a card.

Shimmer Myr

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

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.

Patriarch's Bidding

Each player chooses a creature type. Each player returns all creature cards of a type chosen this way from their graveyard to the battlefield.

Myr Kinsmith

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

Misty Rainforest

{T}, Pay 1 life, Sacrifice this land: Search your library for a Forest or Island card, put it onto the battlefield, then shuffle.

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.

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.

Mountain

Myr Retriever

When this creature dies, return another target artifact card from your graveyard to your hand.

Island

Myr Galvanizer

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

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: This creature gets +1/+1 until end of turn.

Verdant Catacombs

{T}, Pay 1 life, Sacrifice this land: Search your library for a Swamp or Forest card, put it onto the battlefield, then shuffle.

Myr Scrapling

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

Leaden Myr

Iron Myr

Polluted Delta

{T}, Pay 1 life, Sacrifice this land: Search your library for an Island or Swamp card, put it onto the battlefield, then shuffle.

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.

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.

Flooded Strand

{T}, Pay 1 life, Sacrifice this land: Search your library for a Plains or Island card, put it onto the battlefield, then shuffle.

Vanquisher's Banner

As this artifact enters, choose a creature type.
Creatures you control of the chosen type get +1/+1.
Whenever you cast a creature spell of the chosen type, draw a card.

Marsh Flats

{T}, Pay 1 life, Sacrifice this land: Search your library for a Plains or Swamp card, put it onto the battlefield, then shuffle.

Sculpting Steel

You may have this artifact enter as a copy of any artifact on the battlefield.

Krark-Clan Ironworks

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.