Dream Twist

Target player mills three cards.
Flashback {1}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Brainstorm

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

Iceberg Cancrix

Whenever another snow permanent you control enters, you may have target player mill two cards.

Thought Scour

Target player mills two cards.
Draw a card.

Annul

Counter target artifact or enchantment spell.

Spell Pierce

Counter target noncreature spell unless its controller pays {2}.

Memory Sluice

Target player mills four cards.
Conspire (As you cast this spell, you may tap two untapped creatures you control that share a color with it. When you do, copy it and you may choose a new target for the copy.)

Preordain

Scry 2, then draw a card. (To scry 2, look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Winds of Rebuke

Return target nonland permanent to its owner's hand. Each player mills two cards.

Snow-Covered Island

Mind Sculpt

Curfew

Each player returns a creature they control to its owner's hand.

Jace's Erasure

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

Tome Scour

Shriekgeist

Flying
Whenever this creature deals combat damage to a player, that player mills two cards.

Tolarian Terror

This spell costs {1} less to cast for each instant and sorcery card in your graveyard.
Ward {2} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {2}.)

Ponder

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

Counterspell

Venture Deeper

Target player mills four cards. (Then exile this card. You may cast the creature later from exile.)

Merfolk Secretkeeper

Merfolk Secretkeeper // Venture Deeper

Jace's Phantasm

Flying
This creature gets +4/+4 as long as an opponent has ten or more cards in their graveyard.

Broken Ambitions

Counter target spell unless its controller pays {X}. Clash with an opponent. If you win, that spell's controller mills four cards. (Each clashing player reveals the top card of their library, then puts that card on the top or bottom. A player wins if their card had a higher mana value.)