Set Adrift

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)
Put target nonland permanent on top of its owner's library.

Dandân

Dandân can't attack unless defending player controls an Island.
When you control no Islands, sacrifice Dandân.

Piracy Charm

Choose one —
• Target creature gains islandwalk until end of turn. (It can't be blocked as long as defending player controls an Island.)
• Target creature gets +2/-1 until end of turn.
• Target player discards a card.

Dissipate

Counter target spell. If that spell is countered this way, exile it instead of putting it into its owner's graveyard.

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.

Counterspell

Sea God's Revenge

Return up to three target creatures your opponents control to their owners' hands. Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Memory Lapse

Counter target spell. If that spell is countered this way, put it on top of its owner's library instead of into that player's graveyard.

Diminishing Returns

Each player shuffles their hand and graveyard into their library. You exile the top ten cards of your library. Then each player draws up to seven cards.

Unwind

Counter target noncreature spell. Untap up to three lands.

Waterwhirl

Return up to two target creatures to their owners' hands.

Treasure Cruise

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)
Draw three cards.

Inevitable Betrayal

Suspend 3—{1}{U}{U} (Rather than cast this card from your hand, pay {1}{U}{U} and exile it with three time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost.)
Search target opponent's library for a creature card and put that card onto the battlefield under your control. Then that player shuffles.

Blinding Spray

Creatures your opponents control get -4/-0 until end of turn.
Draw a card.

Horribly Awry

Devoid (This card has no color.)
Counter target creature spell with mana value 4 or less. If that spell is countered this way, exile it instead of putting it into its owner's graveyard.

Unsubstantiate

Return target spell or creature to its owner's hand.

Lucid Dreams

Draw X cards, where X is the number of card types among cards in your graveyard.

Founding the Third Path

Read ahead (Choose a chapter and start with that many lore counters. Add one after your draw step. Skipped chapters don't trigger. Sacrifice after III.)
I — You may cast an instant or sorcery spell with mana value 1 or 2 from your hand without paying its mana cost.
II — Target player mills four cards.
III — Exile target instant or sorcery card from your graveyard. Copy it. You may cast the copy.

Sudden Insight

Draw a card for each different mana value among nonland cards in your graveyard.

Stubborn Denial

Counter target noncreature spell unless its controller pays {1}.
Ferocious — If you control a creature with power 4 or greater, counter that spell instead.

Downsize

Target creature you don't control gets -4/-0 until end of turn.
Overload {2}{U} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Island

Ertai's Scorn

This spell costs {U} less to cast if an opponent cast two or more spells this turn.
Counter target spell.

Time of Ice

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I, II — Tap target creature an opponent controls. It doesn't untap during its controller's untap step for as long as you control Time of Ice.
III — Return all tapped creatures to their owners' hands.

Ensnare

You may return two Islands you control to their owner's hand rather than pay this spell's mana cost.
Tap all creatures.

Timetwister

Each player shuffles their hand and graveyard into their library, then draws seven cards. (Then put Timetwister into its owner's graveyard.)

Confiscate

Enchant permanent
You control enchanted permanent.

Hurkyl's Final Meditation

During turns other than yours, this spell costs {3} more to cast.
Return all nonland permanents to their owners' hands. End the turn. (Exile all spells and abilities from the stack, including this card. The player whose turn it is discards down to their maximum hand size. Damage wears off, and "this turn" and "until end of turn" effects end.)

Accumulated Knowledge

Draw a card, then draw cards equal to the number of cards named Accumulated Knowledge in all graveyards.

Treasure Hunt

Reveal cards from the top of your library until you reveal a nonland card, then put all cards revealed this way into your hand.

Befuddle

Target creature gets -4/-0 until end of turn.
Draw a card.

Grip of the Roil

Surge {1}{U} (You may cast this spell for its surge cost if you or a teammate has cast another spell this turn.)
Tap target creature. It doesn't untap during its controller's next untap step.
Draw a card.

Bitter Chill

Enchant creature
When Bitter Chill enters, tap enchanted creature.
Enchanted creature doesn't untap during its controller's untap step.
When Bitter Chill is put into a graveyard from the battlefield, you may pay {1}. If you do, scry 1, then draw a card.

Medomai's Prophecy

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after IV.)
I — Scry 2.
II — Choose a card name.
III — When you cast a spell with the chosen name for the first time this turn, draw two cards.
IV — Look at the top card of each player's library.

Dissolve

Counter target spell. Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Interpret the Signs

Scry 3, then reveal the top card of your library. Draw cards equal to that card's mana value. (To scry 3, look at the top three cards of your library, then put any number of them on the bottom and the rest on top in any order.)