Spiny Starfish

{U}: Regenerate Spiny Starfish.
At the beginning of each end step, if Spiny Starfish regenerated this turn, create a 0/1 blue Starfish creature token for each time it regenerated this turn.

Wall of Lost Thoughts

Defender (This creature can't attack.)
When Wall of Lost Thoughts enters, target player mills four cards. (They put the top four cards of their library into their graveyard.)

Traumatize

Target player mills half their library, rounded down.

Ponder

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

Kraken's Eye

Whenever a player casts a blue spell, you may gain 1 life.

Spellbook

Thought Scour

Target player mills two cards.
Draw a card.

Mind Spring

Thought Collapse

Counter target spell. Its controller mills three cards.

Wall of Frost

Defender
Whenever Wall of Frost blocks a creature, that creature doesn't untap during its controller's next untap step.

Ruin Crab

Landfall — Whenever a land you control enters, each opponent mills three cards. (To mill a card, a player puts the top card of their library into their graveyard.)

Tempest Caller

When Tempest Caller enters, tap all creatures target opponent controls.

Patient Rebuilding

At the beginning of your upkeep, target opponent mills three cards, then you draw a card for each land card put into their graveyard this way.

Tormod's Crypt

{T}, Sacrifice Tormod's Crypt: Exile target player's graveyard.

Elixir of Immortality

{2}, {T}: You gain 5 life. Shuffle Elixir of Immortality and your graveyard into their owner's library.

Borrowing 100,000 Arrows

Draw a card for each tapped creature target opponent controls.

Memory Erosion

Whenever an opponent casts a spell, that player mills two cards.

Visions of Beyond

Draw a card. If a graveyard has twenty or more cards in it, draw three cards instead.

Island

Propaganda

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

Jace's Erasure

Whenever you draw a card, you may have target player mill a card.

Didn't Say Please

Psychic Corrosion

Whenever you draw a card, each opponent mills two cards.

Tome Scour

Errant, Street Artist

Flash
Defender, haste
{1}{U}, {T}: Copy target spell you control that wasn't cast. You may choose new targets for the copy.

Brainstorm

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

Aetherize

Return all attacking creatures to their owner's hand.

Meekstone

Creatures with power 3 or greater don't untap during their controllers' untap steps.

Sphinx's Tutelage

Whenever you draw a card, target opponent mills two cards. If two nonland cards that share a color were milled this way, repeat this process.
{5}{U}: Draw a card, then discard a card.

Sapphire Medallion

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

Mind Sculpt

Glacial Grasp

Tap target creature. Its controller mills two cards. That creature doesn't untap during its controller's next untap step. (They put the top two cards of their library into their graveyard.)
Draw a card.

Curse of the Bloody Tome

Enchant player
At the beginning of enchanted player's upkeep, that player mills two cards.

Twincast

Copy target instant or sorcery spell. You may choose new targets for the copy.

Staff of the Mind Magus

Whenever you cast a blue spell or an Island you control enters, you gain 1 life.