Have

Persistent Petitioners

{1}, {T}: Target player mills a card. (They put the top card of their library into their graveyard.)
Tap four untapped Advisors you control: Target player mills twelve cards.
A deck can have any number of cards named Persistent Petitioners.

Midnight Clock

{T}: Add {U}.
{2}{U}: Put an hour counter on this artifact.
At the beginning of each upkeep, put an hour counter on this artifact.
When the twelfth hour counter is put on this artifact, shuffle your hand and graveyard into your library, then draw seven cards. Exile this artifact.

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.

Riddlekeeper

Whenever a creature attacks you or a planeswalker you control, that creature's controller mills two cards.

Essential

Archaeomancer

When this creature enters, return target instant or sorcery card from your graveyard to your hand.

Nykthos, Shrine to Nyx

{T}: Add {C}.
{2}, {T}: Choose a color. Add an amount of mana of that color equal to your devotion to that color. (Your devotion to a color is the number of mana symbols of that color in the mana costs of permanents you control.)

Profane Memento

Whenever a creature card is put into an opponent's graveyard from anywhere, you gain 1 life.

Fleet Swallower

Whenever this creature attacks, target player mills half their library, rounded up.

Phyrexian Germ

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.

Unstoppable Plan

At the beginning of your end step, untap all nonland permanents you control.

Jace's Mindseeker

Flying
When this creature enters, target opponent mills five cards. You may cast an instant or sorcery spell from among them without paying its mana cost.

Lightning Greaves

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.)
Equip {0}

Fractured Sanity

Each opponent mills fourteen cards.
Cycling {1}{U} ({1}{U}, Discard this card: Draw a card.)
When you cycle this card, each opponent mills four cards.

Veteran Ice Climber

Vigilance
This creature can't be blocked.
Whenever this creature attacks, up to one target player mills cards equal to this creature's power. (They put that many cards from the top of their library into their graveyard.)

Psychic Corrosion

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

Mystical Tutor

Search your library for an instant or sorcery card, reveal it, then shuffle and put that card on top.

Sapphire Medallion

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

Didn't Say Please

Counter target spell. Its controller mills three cards.

Unwind

Counter target noncreature spell. Untap up to three lands.

Thought Scour

Target player mills two cards.
Draw a card.

Thassa's Rebuff

Counter target spell unless its controller pays {X}, where X is your devotion to blue. (Each {U} in the mana costs of permanents you control counts toward your devotion to blue.)

Jace's Phantasm

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

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control. It can attack and {T} no matter when it came under your control.)
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Psychic Barrier

Counter target creature spell. Its controller loses 1 life.

Chronic Flooding

Enchant land
Whenever enchanted land becomes tapped, its controller mills three cards.

Conjurer's Closet

At the beginning of your end step, you may exile target creature you control, then return that card to the battlefield under your control.

Magistrate's Scepter

{4}, {T}: Put a charge counter on this artifact.
{T}, Remove three charge counters from this artifact: Take an extra turn after this one.

Overwhelmed Apprentice

When this creature enters, each opponent mills two cards. Then you 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.)

Countermand

Counter target spell. Its controller mills four cards.

Counterspell

Kindred Discovery

As this enchantment enters, choose a creature type.
Whenever a creature you control of the chosen type enters or attacks, draw a card.

Sol Ring

Traumatize

Target player mills half their library, rounded down.

Tome Scour

Bonehoard

Living weapon (When this Equipment enters, create a 0/0 black Phyrexian Germ creature token, then attach this to it.)
Equipped creature gets +X/+X, where X is the number of creature cards in all graveyards.
Equip {2}

Mana Leak

Counter target spell unless its controller pays {3}.

High Tide

Until end of turn, whenever a player taps an Island for mana, that player adds an additional {U}.

Manic Scribe

When this creature enters, each opponent mills three cards.
Delirium — At the beginning of each opponent's upkeep, if there are four or more card types among cards in your graveyard, that player mills three cards.

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.

Meletis Charlatan

{2}{U}, {T}: The controller of target instant or sorcery spell copies it. That player may choose new targets for the copy.

Bruvac the Grandiloquent

If an opponent would mill one or more cards, they mill twice that many cards instead. (To mill a card, a player puts the top card of their library into their graveyard.)

Reliquary Tower

You have no maximum hand size.
{T}: Add {C}.

Mind Sculpt

Levitation

Blue Sun's Zenith

Target player draws X cards. Shuffle Blue Sun's Zenith into its owner's library.

Maddening Cacophony

Kicker {3}{U}
Each opponent mills eight cards. If this spell was kicked, instead each opponent mills half their library, rounded up.