Mountain

Minamo, School at Water's Edge

{T}: Add {U}.
{U}, {T}: Untap target legendary permanent.

Mindmoil

Whenever you cast a spell, put the cards in your hand on the bottom of your library in any order, then draw that many cards.

Dualcaster Mage

Flash
When Dualcaster Mage enters, copy target instant or sorcery spell. You may choose new targets for the copy.

Compulsive Research

Target player draws three cards. Then that player discards two cards unless they discard a land card.

Time Warp

Target player takes an extra turn after this one.

Agate Instigator

Offspring {1}{R} (You may pay an additional {1}{R} as you cast this spell. If you do, when this creature enters, create a 1/1 token copy of it.)
Whenever another creature you control enters, this creature deals 1 damage to each opponent.

Long River's Pull

Gift a card (You may promise an opponent a gift as you cast this spell. If you do, they draw a card before its other effects.)
Counter target creature spell. If the gift was promised, instead counter target spell.

Narset's Reversal

Copy target instant or sorcery spell, then return it to its owner's hand. You may choose new targets for the copy.

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.)

Kira, Great Glass-Spinner

Flying
Creatures you control have "Whenever this creature becomes the target of a spell or ability for the first time each turn, counter that spell or ability."

Alhammarret's Archive

If you would gain life, you gain twice that much life instead.
If you would draw a card except the first one you draw in each of your draw steps, draw two cards instead.

Skullclamp

Equipped creature gets +1/-1.
Whenever equipped creature dies, draw two cards.
Equip {1}

Might get rid of

Venser's Journal

You have no maximum hand size.
At the beginning of your upkeep, you gain 1 life for each card in your hand.

Izzet Signet

Frantic Search

Draw two cards, then discard two cards. Untap up to three lands.

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.

Niv-Mizzet, Parun

This spell can't be countered.
Flying
Whenever you draw a card, Niv-Mizzet, Parun deals 1 damage to any target.
Whenever a player casts an instant or sorcery spell, you draw a card.

Brainsurge

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

Keep Watch

Exotic Orchard

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

Ral, Leyline Prodigy

Ral, Leyline Prodigy enters with an additional loyalty counter on him for each instant and sorcery spell you've cast this turn.
+1: Until your next turn, instant and sorcery spells you cast cost {1} less to cast.
−2: Ral deals 2 damage divided as you choose among one or two targets. Draw a card if you control a blue permanent other than Ral.
−8: Exile the top eight cards of your library. You may cast instant and sorcery spells from among them this turn without paying their mana costs.

Ral, Monsoon Mage

Instant and sorcery spells you cast cost {1} less to cast.
Whenever you cast an instant or sorcery spell during your turn, flip a coin. If you lose the flip, Ral, Monsoon Mage deals 1 damage to you. If you win the flip, you may exile Ral. If you do, return him to the battlefield transformed under his owner's control.

Ral, Monsoon Mage // Ral, Leyline Prodigy

Consider

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

Day's Undoing

Each player shuffles their hand and graveyard into their library, then draws seven cards. If it's your turn, end the turn. (Exile all spells and abilities from the stack, including this card. Discard down to your maximum hand size. Damage wears off, and "this turn" and "until end of turn" effects end.)

Proft's Eidetic Memory

When Proft's Eidetic Memory enters, draw a card.
You have no maximum hand size.
At the beginning of combat on your turn, if you've drawn more than one card this turn, put X +1/+1 counters on target creature you control, where X is the number of cards you've drawn this turn minus one.

Flare of Duplication

You may sacrifice a nontoken red creature rather than pay this spell's mana cost.
Copy target instant or sorcery spell. You may choose new targets for the copy.

Phyrexian Altar

Sacrifice a creature: Add one mana of any color.

Winds of Change

Each player shuffles the cards from their hand into their library, then draws that many cards.

Squid

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)

Shivan Reef

{T}: Add {C}.
{T}: Add {U} or {R}. Shivan Reef deals 1 damage to you.

Swarm Intelligence

Whenever you cast an instant or sorcery spell, you may copy that spell. You may choose new targets for the copy.

Jace's Archivist

{U}, {T}: Each player discards their hand, then draws cards equal to the greatest number of cards a player discarded this way.

Counterflux

This spell can't be countered.
Counter target spell you don't control.
Overload {1}{U}{U}{R} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Don't Have

Fierce Guardianship

If you control a commander, you may cast this spell without paying its mana cost.
Counter target noncreature spell.

Mystic Remora

Cumulative upkeep {1} (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)
Whenever an opponent casts a noncreature spell, you may draw a card unless that player pays {4}.

Doublecast

When you next cast an instant or sorcery spell this turn, copy that spell. You may choose new targets for the copy.

Ancient Silver Dragon

Flying
Whenever Ancient Silver Dragon deals combat damage to a player, roll a d20. Draw cards equal to the result. You have no maximum hand size for the rest of the game.

Jace, Wielder of Mysteries

If you would draw a card while your library has no cards in it, you win the game instead.
+1: Target player mills two cards. Draw a card.
−8: Draw seven cards. Then if your library has no cards in it, you win the game.

Teferi's Ageless Insight

If you would draw a card except the first one you draw in each of your draw steps, draw two cards instead.

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.

Insect

Repeated Reverberation

When you next cast an instant spell, cast a sorcery spell, or activate a loyalty ability this turn, copy that spell or ability twice. You may choose new targets for the copies.

Humble Defector

{T}: Draw two cards. Target opponent gains control of Humble Defector. Activate only during your turn.

Increasing Vengeance

Copy target instant or sorcery spell you control. If this spell was cast from a graveyard, copy that spell twice instead. You may choose new targets for the copies.
Flashback {3}{R}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Gitaxian Probe

({U/P} can be paid with either {U} or 2 life.)
Look at target player's hand.
Draw a card.

Copy Enchantment

You may have Copy Enchantment enter as a copy of any enchantment on the battlefield.

Burn at the Stake

As an additional cost to cast this spell, tap any number of untapped creatures you control.
Burn at the Stake deals damage to any target equal to three times the number of creatures tapped this way.

Vandalblast

Destroy target artifact you don't control.
Overload {4}{R} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Impact Tremors

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

Narset, Parter of Veils

Each opponent can't draw more than one card each turn.
−2: Look at the top four cards of your library. You may reveal a noncreature, nonland card from among them and put it into your hand. Put the rest on the bottom of your library in a random order.

Shared Animosity

Whenever a creature you control attacks, it gets +1/+0 until end of turn for each other attacking creature that shares a creature type with it.

Halimar Depths

Halimar Depths enters tapped.
When Halimar Depths enters, look at the top three cards of your library, then put them back in any order.
{T}: Add {U}.

Battle Hymn

Mind Stone

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

Commander's Sphere

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

Teferi, Master of Time

You may activate loyalty abilities of Teferi, Master of Time on any player's turn any time you could cast an instant.
+1: Draw a card, then discard a card.
−3: Target creature you don't control phases out. (Treat it and anything attached to it as though they don't exist until its controller's next turn.)
−10: Take two extra turns after this one.

Mystic Sanctuary

({T}: Add {U}.)
Mystic Sanctuary enters tapped unless you control three or more other Islands.
When Mystic Sanctuary enters untapped, you may put target instant or sorcery card from your graveyard on top of your library.

Dramatic Reversal

Untap all nonland permanents you control.

Counterspell

Lavaglide Pathway

Riverglide Pathway

Riverglide Pathway // Lavaglide Pathway

River Song's Diary

Imprint — Whenever a player casts an instant or sorcery spell from their hand, exile it instead of putting it into a graveyard as it resolves.
At the beginning of your upkeep, if there are four or more cards exiled with River Song's Diary, choose one of them at random. You may cast it without paying its mana cost.

Tolarian Winds

Discard all the cards in your hand, then draw that many cards.

Calculated Dismissal

Counter target spell unless its controller pays {3}.
Spell mastery — If there are two or more instant and/or sorcery cards in your graveyard, scry 2. (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.)

Valakut Stoneforge

Valakut Stoneforge enters tapped.
{T}: Add {R}.

Valakut Awakening

Put any number of cards from your hand on the bottom of your library, then draw that many cards plus one.

Valakut Awakening // Valakut Stoneforge

Sol Ring

Ponder

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

Disrupt

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

Mana Drain

Counter target spell. At the beginning of your next main phase, add an amount of {C} equal to that spell's mana value.

Cyclonic Rift

Return target nonland permanent you don't control to its owner's hand.
Overload {6}{U} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Arcane Signet

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

Niv-Mizzet, the Firemind

Flying
Whenever you draw a card, Niv-Mizzet, the Firemind deals 1 damage to any target.
{T}: Draw a card.

Whirlpool Warrior

When Whirlpool Warrior enters, shuffle the cards from your hand into your library, then draw that many cards.
{R}, Sacrifice Whirlpool Warrior: Each player shuffles the cards from their hand into their library, then draws that many cards.

Stormcatch Mentor

Haste
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Instant and sorcery spells you cast cost {1} less to cast.

Whirlpool Rider

When Whirlpool Rider enters, shuffle the cards from your hand into your library, then draw that many cards.

Fork

Copy target instant or sorcery spell, except that the copy is red. You may choose new targets for the copy.

Decanter of Endless Water

You have no maximum hand size.
{T}: Add one mana of any color.

Mindwrack Liege

Other blue creatures you control get +1/+1.
Other red creatures you control get +1/+1.
{U/R}{U/R}{U/R}{U/R}: You may put a blue or red creature card from your hand onto the battlefield.

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.)

Capsize

Buyback {3} (You may pay an additional {3} as you cast this spell. If you do, put this card into your hand as it resolves.)
Return target permanent to its owner's hand.

Curiosity

Enchant creature
Whenever enchanted creature deals damage to an opponent, you may draw a card.

Coat of Arms

Each creature gets +1/+1 for each other creature on the battlefield that shares at least one creature type with it. (For example, if two Goblin Warriors and a Goblin Shaman are on the battlefield, each gets +2/+2.)

Lightning Greaves

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.)
Equip {0}

Sage of the Falls

Whenever Sage of the Falls or another non-Human creature you control enters, you may draw a card. If you do, discard a card.

Sapphire Medallion

Blue spells you cast cost {1} less to cast.

Thought Vessel

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

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.

Amphibian Downpour

Flash
Storm (When you cast this spell, copy it for each spell cast before it this turn. You may choose new targets for the copies. Copies become tokens.)
Enchant creature
Enchanted creature loses all abilities and is a blue Frog creature with base power and toughness 1/1.

Windfall

Each player discards their hand, then draws cards equal to the greatest number of cards a player discarded this way.

Distant Melody

Choose a creature type. Draw a card for each permanent you control of that type.

Flare of Denial

You may sacrifice a nontoken blue creature rather than pay this spell's mana cost.
Counter target spell.

Psychic Corrosion

Whenever you draw a card, each opponent mills two cards.

Magnus the Red

Flying
Unearthly Power — Instant and sorcery spells you cast cost {1} less to cast for each creature token you control.
Blade of Magnus — Whenever Magnus the Red deals combat damage to a player, create a 3/3 red Spawn creature token.

Deflecting Swat

If you control a commander, you may cast this spell without paying its mana cost.
You may choose new targets for target spell or ability.

Teferi's Puzzle Box

At the beginning of each player's draw step, that player puts the cards in their hand on the bottom of their library in any order, then draws that many cards.

Mizzix's Mastery

Exile target card that's an instant or sorcery from your graveyard. For each card exiled this way, copy it, and you may cast the copy without paying its mana cost. Exile Mizzix's Mastery.
Overload {5}{R}{R}{R} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Reliquary Tower

Steam Vents

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

Izzet Boilerworks

Izzet Boilerworks enters tapped.
When Izzet Boilerworks enters, return a land you control to its owner's hand.
{T}: Add {U}{R}.

Echo of Eons

Each player shuffles their hand and graveyard into their library, then draws seven cards.
Flashback {2}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Brainstorm

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