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.

Remote Isle

This land enters tapped.
{T}: Add {U}.
Cycling {2} ({2}, Discard this card: Draw a card.)

Lonely Sandbar

This land enters tapped.
{T}: Add {U}.
Cycling {U} ({U}, Discard this card: Draw a card.)

Dandân

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

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.

Crystal Spray

Change the text of target spell or permanent by replacing all instances of one color word with another or one basic land type with another until end of turn.
Draw a card.

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.

Unsubstantiate

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

Halimar Depths

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

Metamorphose

Put target permanent an opponent controls on top of its owner's library. That opponent may put an artifact, creature, enchantment, or land card from their hand onto the battlefield.

Accumulated Knowledge

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

Predict

Choose a card name, then target player mills a card. If a card with the chosen name was milled this way, you draw two cards. Otherwise, you draw a card.

Dimir Aqueduct

This land enters tapped.
When this land enters, return a land you control to its owner's hand.
{T}: Add {U}{B}.

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.

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.

Island

Supplant Form

Return target creature to its owner's hand. You create a token that's a copy of that creature.

Thought Scour

Target player mills two cards.
Draw a card.

Temple of Deceit

This land enters tapped.
When this land enters, scry 1. (Look at the top card of your library. You may put that card on the bottom.)
{T}: Add {U} or {B}.

Nascent Metamorph

Whenever this creature attacks or blocks, target opponent reveals cards from the top of their library until they reveal a creature card. This creature becomes a copy of that card until end of turn. Then that player puts all cards revealed this way on the bottom of their library in a random order.

Vision Charm

Choose one —
• Target player mills four cards.
• Choose a land type and a basic land type. Each land of the first chosen type becomes the second chosen type until end of turn.
• Target artifact phases out. (While it's phased out, it's treated as though it doesn't exist. It phases in before its controller untaps during their next untap step.)

Svyelunite Temple

This land enters tapped.
{T}: Add {U}.
{T}, Sacrifice this land: Add {U}{U}.

Brainstorm

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

Ray of Command

Untap target creature an opponent controls and gain control of it until end of turn. That creature gains haste until end of turn. When you lose control of the creature, tap it.

Forbidden Alchemy

Look at the top four cards of your library. Put one of them into your hand and the rest into your graveyard.
Flashback {6}{B} (You may cast this card from your graveyard for its flashback cost. Then exile it.)