Ever-Watching Threshold

Whenever an opponent attacks, if they attacked you and/or a planeswalker you control, draw a card.

Wonder

Flying
As long as Wonder is in your graveyard and you control an Island, creatures you control have flying.

Tolarian Winds

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

Eaten by Piranhas

Flash
Enchant creature
Enchanted creature loses all abilities and is a black Skeleton creature with base power and toughness 1/1. (It loses all other card types and creature types.)

Archmage Emeritus

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

Consecrated Sphinx

Flying
Whenever an opponent draws a card, you may draw two cards.

Junk Winder

Affinity for tokens (This spell costs {1} less to cast for each token you control.)
Whenever a token enters the battlefield under your control, tap target nonland permanent an opponent controls. It doesn't untap during its controller's next untap step.

Flux Channeler

Whenever you cast a noncreature spell, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Aetherize

Return all attacking creatures to their owner's hand.

Ashnod's Altar

Consider

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

Titan of Littjara

As Titan of Littjara enters the battlefield, choose a creature type.
Titan of Littjara is the chosen type in addition to its other types.
Whenever Titan of Littjara enters the battlefield or attacks, you may draw a card for each other creature you control that shares a creature type with it. If you do, discard a card.

Reliquary Tower

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

Rhystic Study

Whenever an opponent casts a spell, you may draw a card unless that player pays {1}.

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}.

Phyrexian Altar

Sacrifice a creature: Add one mana of any color.

Drowned Rusalka

{U}, Sacrifice a creature: Discard a card, then draw a card.

Sapphire Medallion

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

The One Ring

Indestructible
When The One Ring enters the battlefield, if you cast it, you gain protection from everything until your next turn.
At the beginning of your upkeep, you lose 1 life for each burden counter on The One Ring.
{T}: Put a burden counter on The One Ring, then draw a card for each burden counter on The One Ring.

Negate

Psychosis Crawler

Psychosis Crawler's power and toughness are each equal to the number of cards in your hand.
Whenever you draw a card, each opponent loses 1 life.

Blue Sun's Zenith

Target player draws X cards. Shuffle Blue Sun's Zenith into its owner's library.

Midnight Clock

{T}: Add {U}.
{2}{U}: Put an hour counter on Midnight Clock.
At the beginning of each upkeep, put an hour counter on Midnight Clock.
When the twelfth hour counter is put on Midnight Clock, shuffle your hand and graveyard into your library, then draw seven cards. Exile Midnight Clock.

Sky Diamond

Sky Diamond enters the battlefield tapped.
{T}: Add {U}.

Teferi, Temporal Pilgrim

Whenever you draw a card, put a loyalty counter on Teferi, Temporal Pilgrim.
0: Draw a card.
−2: Create a 2/2 blue Spirit creature token with vigilance and "Whenever you draw a card, put a +1/+1 counter on this creature."
−12: Target opponent chooses a permanent they control and returns it to its owner's hand. Then they shuffle each nonland permanent they control into its owner's library.

Transcendent Message

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
Draw X cards.

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 Eldrazi Monument.

Mystic Sanctuary

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

The Golden Throne

Arcane Life-support — If you would lose the game, instead exile The Golden Throne and your life total becomes 1.
A Thousand Souls Die Every Day — {T}, Sacrifice a creature: Add three mana in any combination of colors.

Caged Sun

As Caged Sun enters the battlefield, choose a color.
Creatures you control of the chosen color get +1/+1.
Whenever a land's ability causes you to add one or more mana of the chosen color, add one additional mana of that color.

Ice Out

Bargain (You may sacrifice an artifact, enchantment, or token as you cast this spell.)
This spell costs {1} less to cast if it's bargained.
Counter target spell.

Psychic Possession

Enchant opponent
Skip your draw step.
Whenever enchanted opponent draws a card, you may draw a card.

Nykthos, Shrine to Nyx

{T}: Add {C}.
{2}, {T}: Choose a color. Add an amount of mana of that color equal to your devotion to that color. (Your devotion to a color is the number of mana symbols of that color in the mana costs of permanents you control.)

Nadir Kraken

Whenever you draw a card, you may pay {1}. If you do, put a +1/+1 counter on Nadir Kraken and create a 1/1 blue Tentacle creature token.

Chasm Skulker

Whenever you draw a card, put a +1/+1 counter on Chasm Skulker.
When Chasm Skulker dies, create X 1/1 blue Squid creature tokens with islandwalk, where X is the number of +1/+1 counters on Chasm Skulker. (They can't be blocked as long as defending player controls an Island.)

High Tide

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

Rapid Hybridization

Destroy target creature. It can't be regenerated. That creature's controller creates a 3/3 green Frog Lizard creature token.

Wavebreak Hippocamp

Whenever you cast your first spell during each opponent's turn, draw a card.

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.")

Opposition

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

The Watcher in the Water

The Watcher in the Water enters the battlefield tapped with nine stun counters on it. (If a permanent with a stun counter would become untapped, remove one from it instead.)
Whenever you draw a card during an opponent's turn, create a 1/1 blue Tentacle creature token.
Whenever a Tentacle you control dies, untap up to one target Kraken and put a stun counter on up to one target nonland permanent.

Solemn Simulacrum

When Solemn Simulacrum enters the battlefield, you may search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.
When Solemn Simulacrum dies, you may draw a card.

An Offer You Can't Refuse

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

Mind Stone

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

Resculpt

Exile target artifact or creature. Its controller creates a 4/4 blue and red Elemental creature token.

Mikokoro, Center of the Sea

{T}: Add {C}.
{2}, {T}: Each player draws a card.

Wayfarer's Bauble

{2}, {T}, Sacrifice Wayfarer's Bauble: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Skullclamp

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

Verity Circle

Whenever a creature an opponent controls becomes tapped, if it isn't being declared as an attacker, you may draw a card.
{4}{U}: Tap target creature without flying.

Counterspell

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.

Body of Knowledge

Body of Knowledge's power and toughness are each equal to the number of cards in your hand.
You have no maximum hand size.
Whenever Body of Knowledge is dealt damage, draw that many cards.

Temple of the False God

{T}: Add {C}{C}. Activate only if you control five or more lands.

Arcane Signet

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

Island

Heraldic Banner

As Heraldic Banner enters the battlefield, choose a color.
Creatures you control of the chosen color get +1/+0.
{T}: Add one mana of the chosen color.

Perilous Research

Draw two cards, then sacrifice a permanent.

Lonely Sandbar

Lonely Sandbar enters the battlefield tapped.
{T}: Add {U}.
Cycling {U} ({U}, Discard this card: Draw a card.)

Thought Vessel

Wizard Class

(Gain the next level as a sorcery to add its ability.)
You have no maximum hand size.
{2}{U}: Level 2
When this Class becomes level 2, draw two cards.
{4}{U}: Level 3
Whenever you draw a card, put a +1/+1 counter on target creature you control.

Flow of Knowledge

Draw a card for each Island you control, then discard two cards.

Blasting Station

{T}, Sacrifice a creature: Blasting Station deals 1 damage to any target.
Whenever a creature enters the battlefield, you may untap Blasting Station.

Nezahal, Primal Tide

This spell can't be countered.
You have no maximum hand size.
Whenever an opponent casts a noncreature spell, draw a card.
Discard three cards: Exile Nezahal, Primal Tide. Return it to the battlefield tapped under its owner's control at the beginning of the next end step.

Reality Shift

Exile target creature. Its controller manifests the top card of their library. (That player puts the top card of their library onto the battlefield face down as a 2/2 creature. If it's a creature card, it can be turned face up any time for its mana cost.)

Decanter of Endless Water

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

Frantic Search

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

Faerie Mastermind

Flash
Flying
Whenever an opponent draws their second card each turn, you draw a card.
{3}{U}: Each player draws a card.

Rivendell

Rivendell enters the battlefield tapped unless you control a legendary creature.
{T}: Add {U}.
{1}{U}, {T}: Scry 2. Activate only if you control a legendary creature.

Leyline of Anticipation

If Leyline of Anticipation is in your opening hand, you may begin the game with it on the battlefield.
You may cast spells as though they had flash.

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control.)
Equip {1}

War Room

{T}: Add {C}.
{3}, {T}, Pay life equal to the number of colors in your commanders' color identity: Draw a card.

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.

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.

Lightning Greaves

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

Borne Upon a Wind

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

Nesting Grounds

{T}: Add {C}.
{1}, {T}: Move a counter from target permanent you control onto another target permanent. Activate only as a sorcery.

Terrain Generator

{T}: Add {C}.
{2}, {T}: You may put a basic land card from your hand onto the battlefield tapped.

Cyber Conversion

Turn target creature face down. It's a 2/2 Cyberman artifact creature.

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.

Quick Study

High Market

{T}: Add {C}.
{T}, Sacrifice a creature: You gain 1 life.

Misleading Signpost

Flash
When Misleading Signpost enters the battlefield during the declare attackers step, you may reselect which player or permanent target attacking creature is attacking. (It can't attack its controller or their permanents.)
{T}: Add {U}.

Icebreaker Kraken

This spell costs {1} less to cast for each snow land you control.
When Icebreaker Kraken enters the battlefield, artifacts and creatures target opponent controls don't untap during that player's next untap step.
Return three snow lands you control to their owner's hand: Return Icebreaker Kraken to its owner's hand.

Arcanis the Omnipotent

{T}: Draw three cards.
{2}{U}{U}: Return Arcanis the Omnipotent to its owner's hand.

Throne of Eldraine

As Throne of Eldraine enters the battlefield, choose a color.
{T}: Add four mana of the chosen color. Spend this mana only to cast monocolored spells of that color.
{3}, {T}: Draw two cards. Spend only mana of the chosen color to activate this ability.

Meeting of Minds

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
Draw two cards.

Ominous Seas

Whenever you draw a card, put a foreshadow counter on Ominous Seas.
Remove eight foreshadow counters from Ominous Seas: Create an 8/8 blue Kraken creature token.
Cycling {2} ({2}, Discard this card: Draw a card.)

Pongify

Destroy target creature. It can't be regenerated. Its controller creates a 3/3 green Ape creature token.

Otawara, Soaring City

{T}: Add {U}.
Channel — {3}{U}, Discard Otawara, Soaring City: Return target artifact, creature, enchantment, or planeswalker to its owner's hand. This ability costs {1} less to activate for each legendary creature you control.

Keep Watch

Myriad Landscape

Myriad Landscape enters the battlefield 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.

Abjure

As an additional cost to cast this spell, sacrifice a blue permanent.
Counter target spell.

Brainstorm

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