Stifle

Counter target activated or triggered ability. (Mana abilities can't be targeted.)

Library of Leng

You have no maximum hand size.
If an effect causes you to discard a card, discard it, but you may put it on top of your library instead of into your graveyard.

Dramatic Reversal

Untap all nonland permanents you control.

Force of Negation

If it's not your turn, you may exile a blue card from your hand rather than pay this spell's mana cost.
Counter target noncreature spell. If that spell is countered this way, exile it instead of putting it into its owner's graveyard.

Vizier of Tumbling Sands

{T}: Untap another target permanent.
Cycling {1}{U} ({1}{U}, Discard this card: Draw a card.)
When you cycle this card, untap target permanent.

Inventors' Fair

At the beginning of your upkeep, if you control three or more artifacts, you gain 1 life.
{T}: Add {C}.
{4}, {T}, Sacrifice Inventors' Fair: Search your library for an artifact card, reveal it, put it into your hand, then shuffle. Activate only if you control three or more artifacts.

Ioreth of the Healing House

{T}: Untap another target permanent.
{T}: Untap two other target legendary creatures.

Kelpie Guide

{T}: Untap another target permanent you control.
{T}: Tap target permanent. Activate only if you control eight or more lands.

Mystical Tutor

Search your library for an instant or sorcery card, reveal it, then shuffle and put that card on top.

Fatestitcher

{T}: You may tap or untap another target permanent.
Unearth {U} ({U}: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the next end step or if it would leave the battlefield. Unearth only as a sorcery.)

Force of Will

You may pay 1 life and exile a blue card from your hand rather than pay this spell's mana cost.
Counter target spell.

Counterspell

Sol Ring

Thought Vessel

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

Fabricate

Search your library for an artifact card, reveal it, put it into your hand, then shuffle.

Gemstone Caverns

If this card is in your opening hand and you're not the starting player, you may begin the game with Gemstone Caverns on the battlefield with a luck counter on it. If you do, exile a card from your hand.
{T}: Add {C}. If Gemstone Caverns has a luck counter on it, instead add one mana of any color.

Refocus

Arcane Signet

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

Ponder

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

Boomerang Basics

Return target nonland permanent to its owner's hand. If you controlled that permanent, draw a card.

Paradise Mantle

Equipped creature has "{T}: Add one mana of any color."
Equip {1}

Flusterstorm

Counter target instant or sorcery spell unless its controller pays {1}.
Storm (When you cast this spell, copy it for each spell cast before it this turn. You may choose new targets for the copies.)

Mox Opal

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

Words of Wisdom

You draw two cards, then each other player draws a card.

Arcane Denial

Counter target spell. Its controller may draw up to two cards at the beginning of the next turn's upkeep.
You draw a card at the beginning of the next turn's upkeep.

Frantic Search

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

Noble Benefactor

When this creature dies, each player may search their library for a card and put that card into their hand. Then each player who searched their library this way shuffles.

Relic of Legends

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

Borne Upon a Wind

You may cast spells this turn as though they had flash.
Draw a card.

Lotus Petal

{T}, Sacrifice this artifact: Add one mana of any color.

Aang's Journey

Kicker {2} (You may pay an additional {2} as you cast this spell.)
Search your library for a basic land card. If this spell was kicked, instead search your library for a basic land card and a Shrine card. Reveal those cards, put them into your hand, then shuffle.
You gain 2 life.

Springleaf Drum

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

Unctus, Grand Metatect

Other blue creatures you control have "Whenever this creature becomes tapped, draw a card, then discard a card."
Other artifact creatures you control get +1/+1.
{U/P}: Until end of turn, target creature you control becomes a blue artifact in addition to its other colors and types. Activate only as a sorcery. ({U/P} can be paid with either {U} or 2 life.)

Mox Amber

{T}: Add one mana of any color among legendary creatures and planeswalkers you control.

Grim Monolith

This artifact doesn't untap during your untap step.
{T}: Add {C}{C}{C}.
{4}: Untap this artifact.

Accumulate Wisdom

Look at the top three cards of your library. Put one of those cards into your hand and the rest on the bottom of your library in any order. Put each of those cards into your hand instead if there are three or more Lesson cards in your graveyard.

Thassa's Oracle

When this creature enters, look at the top X cards of your library, where X is your devotion to blue. Put up to one of them on top of your library and the rest on the bottom of your library in a random order. If X is greater than or equal to the number of cards in your library, you win the game. (Each {U} in the mana costs of permanents you control counts toward your devotion to blue.)

Waterbender's Restoration

As an additional cost to cast this spell, waterbend {X}. (While paying a waterbend cost, you can tap your artifacts and creatures to help. Each one pays for {1}.)
Exile X target creatures you control. Return those cards to the battlefield under their owner's control at the beginning of the next end step.

Brain Freeze

Target player mills three cards.
Storm (When you cast this spell, copy it for each spell cast before it this turn. You may choose new targets for the copies.)

An Offer You Can't Refuse

Counter target noncreature spell. Its controller creates two Treasure tokens. (They're artifacts with "{T}, Sacrifice this token: Add one mana of any color.")

High Tide

Until end of turn, whenever a player taps an Island for mana, that player adds an additional {U}.

Teachings of the Archaics

If an opponent has more cards in hand than you, draw two cards. Draw three cards instead if an opponent has at least four more cards in hand than you.

Tidespout Tyrant

Flying
Whenever you cast a spell, return target permanent to its owner's hand.

Emergence Zone

{T}: Add {C}.
{1}, {T}, Sacrifice this land: You may cast spells this turn as though they had flash.

Hullbreaker Horror

Flash
This spell can't be countered.
Whenever you cast a spell, choose up to one —
• Return target spell you don't control to its owner's hand.
• Return target nonland permanent to its owner's hand.

Island

Gran-Gran

Whenever Gran-Gran becomes tapped, draw a card, then discard a card.
Noncreature spells you cast cost {1} less to cast as long as there are three or more Lesson cards in your graveyard.

Archaeomancer

When this creature enters, return target instant or sorcery card from your graveyard to your hand.

Snap

Return target creature to its owner's hand. Untap up to two lands.

Reliquary Tower

Illusionist's Bracers

Whenever an ability of equipped creature is activated, if it isn't a mana ability, copy that ability. You may choose new targets for the copy.
Equip {3}

Archmage Emeritus

Magecraft — Whenever you cast or copy an instant or sorcery spell, draw a card.

Everflowing Chalice

Multikicker {2} (You may pay an additional {2} any number of times as you cast this spell.)
This artifact enters with a charge counter on it for each time it was kicked.
{T}: Add {C} for each charge counter on this artifact.

Personal Tutor

Search your library for a sorcery card, reveal it, then shuffle and put that card on top.

Pact of Negation

Counter target spell.
At the beginning of your next upkeep, pay {3}{U}{U}. If you don't, you lose the game.

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.

Clever Conjurer

Mage Hand — {T}: Untap target permanent not named Clever Conjurer. Activate only as a sorcery.

Consider

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

Pemmin's Aura

Enchant creature
{U}: Untap enchanted creature.
{U}: Enchanted creature gains flying until end of turn.
{U}: Enchanted creature gains shroud until end of turn. (It can't be the target of spells or abilities.)
{1}: Enchanted creature gets +1/-1 or -1/+1 until end of turn.

Environmental Sciences

Search your library for a basic land card, reveal it, put it into your hand, then shuffle. You gain 2 life.

Mana Vault

This artifact doesn't untap during your untap step.
At the beginning of your upkeep, you may pay {4}. If you do, untap this artifact.
At the beginning of your draw step, if this artifact is tapped, it deals 1 damage to you.
{T}: Add {C}{C}{C}.

Brainstorm

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

Power Artifact

Enchant artifact
Enchanted artifact's activated abilities cost {2} less to activate. This effect can't reduce the mana in that cost to less than one mana.

Fierce Guardianship

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

Energybending

Lands you control gain all basic land types until end of turn.
Draw a card.

Chrome Mox

Imprint — When this artifact enters, you may exile a nonartifact, nonland card from your hand.
{T}: Add one mana of any of the exiled card's colors.

Portent

Look at the top three cards of target player's library, then put them back in any order. You may have that player shuffle.
Draw a card at the beginning of the next turn's upkeep.

Survivors' Encampment

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

Kitsa, Otterball Elite

Vigilance
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
{T}: Draw a card, then discard a card.
{2}, {T}: Copy target instant or sorcery spell you control. You may choose new targets for the copy. Activate only if Kitsa's power is 3 or greater.

Isochron Scepter

Imprint — When this artifact enters, you may exile an instant card with mana value 2 or less from your hand.
{2}, {T}: You may copy the exiled card. If you do, you may cast the copy without paying its mana cost.

Aphetto Alchemist

{T}: Untap target artifact or creature.
Morph {U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Freed from the Real

Enchant creature
{U}: Tap enchanted creature.
{U}: Untap enchanted creature.

Obsessive Search

Draw a card.
Madness {U} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)

Intuition

Search your library for three cards and reveal them. Target opponent chooses one. Put that card into your hand and the rest into your graveyard. Then shuffle.