Extract from Darkness

Each player mills two cards. Then you put a creature card from a graveyard onto the battlefield under your control.

Thassa’s Devourer

Constellation — Whenever Thassa’s Devourer or another enchantment enters the battlefield under your control, target player mills two cards.

Nyx Weaver

Reach
At the beginning of your upkeep, mill two cards.
, Exile Nyx Weaver: Return target card from your graveyard to your hand.

Countermand

Counter target spell. Its controller mills four cards.

Jace’s Mindseeker

Flying
When Jace’s Mindseeker enters the battlefield, target opponent mills five cards. You may cast an instant or sorcery spell from among them without paying its mana cost.

Crosstown Courier

Whenever Crosstown Courier deals combat damage to a player, that player mills that many cards.

Grisly Spectacle

Destroy target nonartifact creature. Its controller mills cards equal to that creature’s power.

Phenax, God of Deception

Indestructible
As long as your devotion to blue and black is less than seven, Phenax isn’t a creature.
Creatures you control have “: Target player mills X cards, where X is this creature’s toughness.”

Siren of the Silent Song

Flying
Inspired — Whenever Siren of the Silent Song becomes untapped, each opponent discards a card, then each opponent mills a card.

Evanescent Intellect

Enchant creature
Enchanted creature has “, : Target player mills three cards.”

Returned Centaur

When Returned Centaur enters the battlefield, target player mills four cards.

Jace, Memory Adept

+1: Draw a card. Target player mills a card.
0: Target player mills ten cards.
−7: Any number of target players each draw twenty cards.

Jace’s Mindseeker

Flying
When Jace’s Mindseeker enters the battlefield, target opponent mills five cards. You may cast an instant or sorcery spell from among them without paying its mana cost.

Millstone

, : Target player mills two cards.

Traumatize

Target player mills half their library, rounded down.

Jace, Memory Adept

+1: Draw a card. Target player mills a card.
0: Target player mills ten cards.
−7: Any number of target players each draw twenty cards.

Moldervine Cloak

Enchant creature
Enchanted creature gets +3/+3.
Dredge 2 (If you would draw a card, you may mill two cards instead. If you do, return this card from your graveyard to your hand.)

Life from the Loam

Return up to three target land cards from your graveyard to your hand.
Dredge 3 (If you would draw a card, you may mill three cards instead. If you do, return this card from your graveyard to your hand.)

Stinkweed Imp

Flying
Whenever Stinkweed Imp deals combat damage to a creature, destroy that creature.
Dredge 5 (If you would draw a card, you may mill five cards instead. If you do, return this card from your graveyard to your hand.)

Dampen Thought

Target player mills four cards.
Splice onto Arcane (As you cast an Arcane spell, you may reveal this card from your hand and pay its splice cost. If you do, add this card’s effects to that spell.)