Have

Part the Waterveil

Take an extra turn after this one. Exile Part the Waterveil.
Awaken 6—{6}{U}{U}{U} (If you cast this spell for {6}{U}{U}{U}, also put six +1/+1 counters on target land you control and it becomes a 0/0 Elemental creature with haste. It's still a land.)

Flow of Knowledge

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

Throne of Eldraine

As Throne of Eldraine enters, 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.

Towering Viewpoint

Defender, reach
Leap of Faith — {3}: Target creature gains flying until end of turn.

Reality Twist

Cumulative upkeep {1}{U}{U} (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.)
If tapped for mana, Plains produce {R}, Swamps produce {G}, Mountains produce {W}, and Forests produce {B} instead of any other type.

Aetherize

Return all attacking creatures to their owner's hand.

Spectral Deluge

Return each creature your opponents control with toughness X or less to its owner's hand, where X is the number of Islands you control.
Foretell {1}{U}{U} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Sword Coast Sailor

Commander creatures you own have "Whenever this creature attacks a player, if no opponent has more life than that player, this creature can't be blocked this turn."

Filter Out

Return all noncreature, nonland permanents to their owners' hands.

Getting

Eluge, the Shoreless Sea

Eluge's power and toughness are each equal to the number of Islands you control.
Whenever Eluge enters or attacks, put a flood counter on target land. It's an Island in addition to its other types for as long as it has a flood counter on it.
The first instant or sorcery spell you cast each turn costs {U} (or {1}) less to cast for each land you control with a flood counter on it.

Mesmeric Trance

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.)
{U}, Discard a card: Draw a card.

Engulf the Shore

Return to their owners' hands all creatures with toughness less than or equal to the number of Islands you control.

Halls of Mist

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.)
Creatures that attacked during their controller's last turn can't attack.

Snowfall

Cumulative upkeep {U} (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 Island is tapped for mana, its controller may add an additional {U}. If that Island is snow, its controller may add an additional {U}{U} instead. Spend this mana only to pay cumulative upkeep costs.

Snow-Covered Island

Leyline of Anticipation

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

Ferropede

This creature can't be blocked.
Whenever this creature deals combat damage to a player, you may remove a counter from target permanent.

Rapid Hybridization

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

Tidal Control

Cumulative upkeep {2} (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.)
Pay 2 life or {2}: Counter target red or green spell. Any player may activate this ability.

Sapphire Medallion

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

Hydro-Man, Fluid Felon

Whenever you cast a blue spell, if Hydro-Man is a creature, he gets +1/+1 until end of turn.
At the beginning of your end step, untap Hydro-Man. Until your next turn, he becomes a land and gains "{T}: Add {U}." (He's not a creature during that time.)

Assassin Den

Defender (This creature can't attack.)
{3}{U}: Put a +1/+1 counter on target creature you control. It can't be blocked this turn. Activate only as a sorcery.

Library of Lat-Nam

An opponent chooses one —
• You draw three cards at the beginning of the next turn's upkeep.
• You search your library for a card, put that card into your hand, then shuffle.

Propaganda

Creatures can't attack you unless their controller pays {2} for each creature they control that's attacking you.

Floodgate

Defender
When this creature has flying, sacrifice it.
When this creature leaves the battlefield, it deals damage to each nonblue creature without flying equal to half the number of Islands you control, rounded down.

Mnemonic Wall

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

Evacuation

Return all creatures to their owners' hands.

Copy Enchantment

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

Mindsplice Apparatus

Flash
At the beginning of your upkeep, put an oil counter on this artifact.
Instant and sorcery spells you cast cost {1} less to cast for each oil counter on this artifact.

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.)

Breath of Dreams

Cumulative upkeep {U} (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.)
Green creatures have "Cumulative upkeep {1}."

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.

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.

Reliquary Tower

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

Ancestral Knowledge

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.)
When this enchantment enters, look at the top ten cards of your library, then exile any number of them and put the rest back on top of your library in any order.
When this enchantment leaves the battlefield, shuffle your library.

High Fae Trickster

Flash (You may cast this spell any time you could cast an instant.)
Flying
You may cast spells as though they had flash.

Release to the Wind

Exile target nonland permanent. For as long as that card remains exiled, its owner may cast it without paying its mana cost.

Halimar Tidecaller

When this creature enters, you may return target card with awaken from your graveyard to your hand.
Land creatures you control have flying.

Fog Bank

Defender (This creature can't attack.)
Flying
Prevent all combat damage that would be dealt to and dealt by this creature.

Eon Hub

Pongify

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

Imprisoned in the Moon

Enchant creature, land, or planeswalker
Enchanted permanent is a colorless land with "{T}: Add {C}" and loses all other card types and abilities.

Mana Chains

Enchant creature
Enchanted creature has "Cumulative upkeep {1}." (At the beginning of its controller's upkeep, that player puts an age counter on it, then sacrifices it unless they pay its upkeep cost for each age counter on it.)

Wall of Vapor

Defender (This creature can't attack.)
Prevent all damage that would be dealt to this creature by creatures it's blocking.

Mind Harness

Enchant red or green creature
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.)
You control enchanted creature.

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.

Archmage's Charm

Choose one —
• Counter target spell.
• Target player draws two cards.
• Gain control of target nonland permanent with mana value 1 or less.

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.

Laboratory Maniac

If you would draw a card while your library has no cards in it, you win the game instead.

High Tide

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

Scatter to the Winds

Counter target spell.
Awaken 3—{4}{U}{U} (If you cast this spell for {4}{U}{U}, also put three +1/+1 counters on target land you control and it becomes a 0/0 Elemental creature with haste. It's still a land.)

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.")

Musician

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.)
{T}: Put a music counter on target creature. If it doesn't have "At the beginning of your upkeep, destroy this creature unless you pay {1} for each music counter on it," it gains that ability.

Mystic Sanctuary

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

Survivor of the Unseen

Cumulative upkeep {2} (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.)
{T}: Draw two cards, then put a card from your hand on top of your library.

Illusionary Wall

Defender, flying, first strike
Cumulative upkeep {U} (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.)

Caged Sun

As this artifact enters, 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.

Counterspell

Brainstorm

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

Vedalken Orrery

You may cast spells as though they had flash.

Guard Gomazoa

Defender, flying
Prevent all combat damage that would be dealt to this creature.

Estrid's Invocation

You may have this enchantment enter as a copy of an enchantment you control, except it has "At the beginning of your upkeep, you may exile this enchantment. If you do, return it to the battlefield under its owner's control."

Rush of Ice

Tap target creature. It doesn't untap during its controller's next untap step.
Awaken 3—{4}{U} (If you cast this spell for {4}{U}, also put three +1/+1 counters on target land you control and it becomes a 0/0 Elemental creature with haste. It's still a land.)

Midnight Clock

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

Arnjlot's Ascent

Cumulative upkeep {U} (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.)
{1}: Target creature gains flying until end of turn.

Clutch of Currents

Return target creature to its owner's hand.
Awaken 3—{4}{U} (If you cast this spell for {4}{U}, also put three +1/+1 counters on target land you control and it becomes a 0/0 Elemental creature with haste. It's still a land.)

Energy Flux

All artifacts have "At the beginning of your upkeep, sacrifice this artifact unless you pay {2}."

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}.

Coastal Discovery

Draw two cards.
Awaken 4—{5}{U} (If you cast this spell for {5}{U}, also put four +1/+1 counters on target land you control and it becomes a 0/0 Elemental creature with haste. It's still a land.)