Mental Discipline

Disrupt

Counter target instant or sorcery spell unless its controller pays {1}.
Draw a card.

Urza's Tower

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

Mightstone's Animation

Enchant artifact
When this Aura enters, draw a card.
Enchanted artifact is a creature with base power and toughness 4/4 in addition to its other types.

Tower Worker

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

Perilous Vault

{5}, {T}, Exile this artifact: Exile all nonland permanents.

Mind Over Matter

Discard a card: You may tap or untap target artifact, creature, or land.

Take Flight

Enchant creature
Enchanted creature gets +1/+0 and has flying and "Whenever this creature attacks, draw a card."

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.")

Thran Dynamo

Brainstorm

Draw three cards, then put two cards from your hand on top of your library in any order.

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.

Pristine Talisman

Urza's Saga

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — This Saga gains "{T}: Add {C}."
II — This Saga gains "{2}, {T}: Create a 0/0 colorless Construct artifact creature token with 'This token 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.

Su-Chi Cave Guard

Vigilance
Ward {4} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {4}.)
When this creature dies, add eight {C}. Until end of turn, you don't lose this mana as steps and phases end.

Urza's Power Plant

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

Inspiring Statuary

Nonartifact spells you cast have improvise. (Your artifacts can help cast those spells. Each artifact you tap after you're done activating mana abilities pays for {1}.)

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.

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 token becomes the target of a spell, sacrifice it."
−5: Create two tokens that are copies of Jace, except they're not legendary.

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 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 token gets +1/+1 for each artifact you control."
• Scry 1, then draw a card.

Consign to Memory

Replicate {1} (When you cast this spell, copy it for each time you paid its replicate cost. You may choose new targets for the copies.)
Counter target triggered ability or colorless spell.

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 greatest mana value may change the target or targets. If two or more cards are tied for greatest, the target or targets remain unchanged. Changing targets this way doesn't trigger abilities of permanents named Psychic Battle.

Urza's Mine

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

Mine Worker

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

Urza's Tome

{3}, {T}: Draw a card. Then discard a card unless you exile a historic card from your graveyard. (Artifacts, legendaries, and Sagas are historic.)

Candelabra of Tawnos

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.

Opposition

Tap an untapped creature you control: Tap target artifact, creature, or land.

Distant Memories

Search your library for a card, exile it, then shuffle. Any opponent may have you put that card into your hand. If no player does, you draw three cards.

Powerstone Shard

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

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's power, put a +1/+1 counter on Liberator.

Mightstone

Urza's Factory

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

Glasses of Urza

Temporal Aperture

{5}, {T}: Shuffle your library, then reveal the top card. Until end of turn, for as long as that card remains on top of your library, play with the top card of your library revealed and you may play that card without paying its mana cost. (If it has X in its mana cost, X is 0.)

Argivian Avenger

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

Machine Over Matter

This spell costs {1} less to cast if you control an artifact creature.
Return target nonland permanent to its owner's hand.

March of Progress

Choose target artifact creature you control. For each creature chosen this way, create a token that's a copy of it.
Overload {6}{U} (You may cast this spell for its overload cost. If you do, change its text by replacing all instances of "target" with "each.")

Thieving Magpie

Flying (This creature can't be blocked except by creatures with flying or reach.)
Whenever this creature deals damage to an opponent, draw a card.

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.")

Ponder

Look at the top three cards of your library, then put them back in any order. You may shuffle.
Draw a card.

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.

Jalum Tome

{2}, {T}: Draw a card, then discard a card.

Urza's Bauble

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

Beast of Burden

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

Ornithopter

Flux

Each player discards any number of cards, then draws that many cards.
Draw a card.

Urza's Rebuff

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

Urza's Cave

{T}: Add {C}.
{3}, {T}, Sacrifice this land: Search your library for a land card, put it onto the battlefield tapped, then shuffle.