Urza, Lord Protector

Artifact, instant, and sorcery spells you cast cost {1} less to cast.
{7}: If you both own and control Urza, Lord Protector and an artifact named The Mightstone and Weakstone, exile them, then meld them into Urza, Planeswalker. Activate only as a sorcery.

Karn Liberated

+4: Target player exiles a card from their hand.
−3: Exile target permanent.
−14: Restart the game, leaving in exile all non-Aura permanent cards exiled with Karn Liberated. Then put those cards onto the battlefield under your control.

Karn, Scion of Urza

+1: Reveal the top two cards of your library. An opponent chooses one of them. Put that card into your hand and exile the other with a silver counter on it.
−1: Put a card you own with a silver counter on it from exile into your hand.
−2: Create a 0/0 colorless Construct artifact creature token with "This creature gets +1/+1 for each artifact you control."

Worn Powerstone

Worn Powerstone enters tapped.
{T}: Add {C}{C}.

Tolaria West

Tolaria West enters tapped.
{T}: Add {U}.
Transmute {1}{U}{U} ({1}{U}{U}, Discard this card: Search your library for a card with mana value 0, reveal it, put it into your hand, then shuffle. Transmute only as a sorcery.)

Urza's Rebuff

Choose one —
• Counter target spell.
• Tap up to two target creatures.

Splitting the Powerstone

As an additional cost to cast this spell, sacrifice an artifact.
Create two tapped Powerstone tokens. If the sacrificed artifact was legendary, draw a card. (The tokens are artifacts with "{T}: Add {C}. This mana can't be spent to cast a nonartifact spell.")

Power Plant Worker

{3}: Power Plant Worker gets +2/+2 until end of turn. If you control creatures named Mine Worker and Tower Worker, put two +1/+1 counters on Power Plant Worker instead. Activate only once each turn.

Urza's Command

Choose two —
• Creatures you don't control get -2/-0 until end of turn.
• Create a tapped Powerstone token.
• Create a tapped 0/0 colorless Construct artifact creature token with "This creature gets +1/+1 for each artifact you control."
• Scry 1, then draw a card.

Metathran Soldier

Juggernaut

This creature attacks each combat if able.
This creature can't be blocked by Walls.

Urza's Chalice

Whenever a player casts an artifact spell, you may pay {1}. If you do, you gain 1 life.

Mightstone

Academy Ruins

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

Urza's Mine

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

Pristine Talisman

Calamity's Wake

Exile all graveyards. Players can't cast noncreature spells this turn. Exile Calamity's Wake.

Well-Laid Plans

Prevent all damage that would be dealt to a creature by another creature if they share a color.

Urza's Factory

{T}: Add {C}.
{7}, {T}: Create a 2/2 colorless Assembly-Worker artifact creature token.

Pledge of Loyalty

Enchant creature
Enchanted creature has protection from the colors of permanents you control. This effect doesn't remove Pledge of Loyalty.

Beast of Burden

Beast of Burden's power and toughness are each equal to the number of creatures on the battlefield.

Teferi's Moat

As Teferi's Moat enters, choose a color.
Creatures of the chosen color without flying can't attack you.

Tower Worker

Reach
{T}: Add {C}. If you control creatures named Mine Worker and Power Plant Worker, add {C}{C}{C} instead.

Urza's Sylex

{2}{W}{W}, {T}, Exile Urza's Sylex: Each player chooses six lands they control. Destroy all other permanents. Activate only as a sorcery.
When Urza's Sylex is put into exile from the battlefield, you may pay {2}. If you do, search your library for a planeswalker card, reveal it, put it into your hand, then shuffle.

Urza's Armor

If a source would deal damage to you, prevent 1 of that damage.

Urza's Avenger

{0}: Urza's Avenger gets -1/-1 and gains your choice of banding, flying, first strike, or trample until end of turn. (Any creatures with banding, and up to one without, can attack in a band. Bands are blocked as a group. If any creatures with banding you control are blocking or being blocked by a creature, you divide that creature's combat damage, not its controller, among any of the creatures it's being blocked by or is blocking.)

Adarkar Wastes

{T}: Add {C}.
{T}: Add {W} or {U}. Adarkar Wastes deals 1 damage to you.

Nimbus Maze

{T}: Add {C}.
{T}: Add {W}. Activate only if you control an Island.
{T}: Add {U}. Activate only if you control a Plains.

Memorial to Genius

Memorial to Genius enters tapped.
{T}: Add {U}.
{4}{U}, {T}, Sacrifice Memorial to Genius: Draw two cards.

Urza, Powerstone Prodigy

Vigilance
{1}, {T}: Draw a card, then discard a card.
Whenever you discard one or more artifact cards, create a tapped Powerstone token. This ability triggers only once each turn. (The token is an artifact with "{T}: Add {C}. This mana can't be spent to cast a nonartifact spell.")

Urza's Saga

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Urza's Saga gains "{T}: Add {C}."
II — Urza's Saga gains "{2}, {T}: Create a 0/0 colorless Construct artifact creature token with 'This creature gets +1/+1 for each artifact you control.'"
III — Search your library for an artifact card with mana cost {0} or {1}, put it onto the battlefield, then shuffle.

Mantis Engine

{2}: Mantis Engine gains flying until end of turn. (It can't be blocked except by creatures with flying or reach.)
{2}: Mantis Engine gains first strike until end of turn. (It deals combat damage before creatures without first strike.)

Powerstone Shard

{T}: Add {C} for each artifact you control named Powerstone Shard.

Glacial Fortress

Glacial Fortress enters tapped unless you control a Plains or an Island.
{T}: Add {W} or {U}.

Urza, Lord High Artificer

When Urza, Lord High Artificer enters, create a 0/0 colorless Construct artifact creature token with "This creature 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.

Command Tower

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

City of Brass

Whenever City of Brass becomes tapped, it deals 1 damage to you.
{T}: Add one mana of any color.

Hallowed Fountain

({T}: Add {W} or {U}.)
As Hallowed Fountain enters, you may pay 2 life. If you don't, it enters tapped.

Stroke of Genius

Thran Foundry

{1}, {T}, Exile Thran Foundry: Target player shuffles their graveyard into their library.

Urza Assembles the Titans

Read ahead (Choose a chapter and start with that many lore counters. Add one after your draw step. Skipped chapters don't trigger. Sacrifice after III.)
I — Scry 4, then you may reveal the top card of your library. If a planeswalker card is revealed this way, put it into your hand.
II — You may put a planeswalker card with mana value 6 or less from your hand onto the battlefield.
III — You may activate the loyalty abilities of planeswalkers you control twice this turn rather than only once.

Thran Turbine

At the beginning of your upkeep, you may add {C}{C}. You can't spend this mana to cast spells.

Urza's Blueprints

Echo {6} (At the beginning of your upkeep, if this came under your control since the beginning of your last upkeep, sacrifice it unless you pay its echo cost.)
{T}: Draw a card.

Mine Worker

{T}: You gain 1 life. If you control creatures named Power Plant Worker and Tower Worker, you gain 3 life instead.

Sundering Titan

When Sundering Titan enters or leaves the battlefield, choose a land of each basic land type, then destroy those lands.

Spire of Industry

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

Plains

Urza, Prince of Kroog

Artifact creatures you control get +2/+2.
{6}: Create a token that's a copy of target artifact you control, except it's a 1/1 Soldier creature in addition to its other types.

Mana Maze

Players can't cast spells that share a color with the spell most recently cast this turn.

Mental Discipline

Candelabra of Tawnos

Mystic Gate

{T}: Add {C}.
{W/U}, {T}: Add {W}{W}, {W}{U}, or {U}{U}.

Urza's Power Plant

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

The Antiquities War

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I, II — Look at the top five cards of your library. You may reveal an artifact card from among them and put it into your hand. Put the rest on the bottom of your library in a random order.
III — Artifacts you control become artifact creatures with base power and toughness 5/5 until end of turn.

Urza's Bauble

{T}, Sacrifice Urza's Bauble: Look at a card at random in target player's hand. You draw a card at the beginning of the next turn's upkeep.

Island

Planar Collapse

At the beginning of your upkeep, if there are four or more creatures on the battlefield, sacrifice Planar Collapse and destroy all creatures. They can't be regenerated.

Liberator, Urza's Battlethopter

Flash
Flying
You may cast colorless spells and artifact spells as though they had flash.
Whenever you cast a spell, if the amount of mana spent to cast that spell is greater than Liberator, Urza's Battlethopter's power, put a +1/+1 counter on Liberator.

Urza's Tower

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

Psychic Battle

Whenever a player chooses one or more targets, each player reveals the top card of their library. The player who reveals the card with the highest mana value may change the target or targets. If two or more cards are tied for highest, the target or targets remain unchanged. Changing targets this way doesn't trigger abilities of permanents named Psychic Battle.

Argivian Avenger

{1}: Until end of turn, Argivian Avenger gets -1/-1 and gains your choice of flying, vigilance, deathtouch, or haste.

Energy Refractor

When Energy Refractor enters, draw a card.
{2}: Add one mana of any color.

Grapeshot Catapult

{T}: Grapeshot Catapult deals 1 damage to target creature with flying.

Phone a Friend

Call someone and ask them to choose one. If they don't answer, an opponent chooses one. (Don't explain anything else. You choose targets.)
• A — Gain control of target creature you don't control.
• B — Choose target creature you control. Create two tokens that are each copies of it.
• C — Take an extra turn after this one.
• D — Draw seven cards.

Urza's Ruinous Blast

(You may cast a legendary sorcery only if you control a legendary creature or planeswalker.)
Exile all nonland permanents that aren't legendary.

Stern Lesson

Draw two cards, then discard a card. Create a tapped Powerstone token. (It's an artifact with "{T}: Add {C}. This mana can't be spent to cast a nonartifact spell.")

Urza's Fun House

{T}: Add {C}.
{T}: Add {∞}. Activate only once and only if you control an Urza's Mine, an Urza's Power-Plant, and an Urza's Tower.
{7}, {T}: Head to AskUrza.com and click Urza's Fun House.

Hall of Tagsin

{T}: Add {C}.
{1}, {T}: Add one mana of any color.
{4}, {T}: Create a tapped Powerstone token. (It's an artifact with "{T}: Add {C}. This mana can't be spent to cast a nonartifact spell.")

Irrigated Farmland

({T}: Add {W} or {U}.)
Irrigated Farmland enters tapped.
Cycling {2} ({2}, Discard this card: Draw a card.)

Shared Fate

If a player would draw a card, that player exiles the top card of one of their opponents' libraries face down instead.
Each player may look at cards they exiled with Shared Fate, and they may play lands and cast spells from among those cards.

Deserted Beach

Deserted Beach enters tapped unless you control two or more other lands.
{T}: Add {W} or {U}.

Wall of Junk

Defender (This creature can't attack.)
When Wall of Junk blocks, return it to its owner's hand at end of combat. (Return it only if it's on the battlefield.)

The Mightstone and Weakstone

When The Mightstone and Weakstone enters, choose one —
• Draw two cards.
• Target creature gets -5/-5 until end of turn.
{T}: Add {C}{C}. This mana can't be spent to cast nonartifact spells.
(Melds with Urza, Lord Protector.)

Urza's Miter

Whenever an artifact you control is put into a graveyard from the battlefield, if it wasn't sacrificed, you may pay {3}. If you do, draw a card.

Myriad Landscape

Myriad Landscape enters tapped.
{T}: Add {C}.
{2}, {T}, Sacrifice Myriad Landscape: Search your library for up to two basic land cards that share a land type, put them onto the battlefield tapped, then shuffle.

Urza's Workshop

{T}: Add {C}.
Metalcraft — {T}: Add {C} for each Urza's land you control. Activate only if you control three or more artifacts.

Thran Dynamo

Karn, Living Legacy

+1: Create a tapped Powerstone token. (It's an artifact with "{T}: Add {C}. This mana can't be spent to cast a nonartifact spell.")
−1: Pay any amount of mana. Look at that many cards from the top of your library, then put one of those cards into your hand and the rest on the bottom of your library in a random order.
−7: You get an emblem with "Tap an untapped artifact you control: This emblem deals 1 damage to any target."

Urza's Contact Lenses

Urza's Contact Lenses enters tapped.
Urza's Contact Lenses doesn't untap during your untap step.
As long as Urza's Contact Lenses is untapped, all players play with their hands revealed.
Clap your hands twice: You may tap or untap Urza's Contact Lenses.

Jace, Cunning Castaway

+1: Whenever one or more creatures you control deal combat damage to a player this turn, draw a card, then discard a card.
−2: Create a 2/2 blue Illusion creature token with "When this creature becomes the target of a spell, sacrifice it."
−5: Create two tokens that are copies of Jace, Cunning Castaway, except they're not legendary.

Sea of Clouds

Sea of Clouds enters tapped unless you have two or more opponents.
{T}: Add {W} or {U}.

Tablet of Epityr

Whenever an artifact you control is put into a graveyard from the battlefield, you may pay {1}. If you do, you gain 1 life.

Karn, Silver Golem

Whenever Karn, Silver Golem blocks or becomes blocked, it gets -4/+4 until end of turn.
{1}: Target noncreature artifact becomes an artifact creature with power and toughness each equal to its mana value until end of turn.

Blind Seer

{1}{U}: Target spell or permanent becomes the color of your choice until end of turn.

Clay Statue

Perilous Vault

{5}, {T}, Exile Perilous Vault: Exile all nonland permanents.

Urza's Science Fair Project

{2}: Roll a six-sided die. Urza's Science Fair Project gets the indicated result.
1 — It gets -2/-2 until end of turn.
2 — Prevent all combat damage it would deal this turn.
3 — It gains vigilance until end of turn.
4 — It gains first strike until end of turn.
5 — It gains flying until end of turn.
6 — It gets +2/+2 until end of turn.

One with the Multiverse

You may look at the top card of your library any time.
You may play lands and cast spells from the top of your library.
Once during each of your turns, you may cast a spell from your hand or the top of your library without paying its mana cost.

Prairie Stream

({T}: Add {W} or {U}.)
Prairie Stream enters tapped unless you control two or more basic lands.