Disdainful Stroke

Counter target spell with mana value 4 or greater.

Thrumming Stone

Spells you cast have ripple 4. (Whenever you cast a spell, you may reveal the top four cards of your library. You may cast spells with the same name as that spell from among the revealed cards without paying their mana costs. Put the rest on the bottom of your library.)

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.

Sapphire Medallion

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

Crawlspace

No more than two creatures can attack you each combat.

Kefnet's Monument

Blue creature spells you cast cost {1} less to cast.
Whenever you cast a creature spell, target creature an opponent controls doesn't untap during its controller's next untap step.

Cancel

The Mindskinner

The Mindskinner can't be blocked.
If a source you control would deal damage to an opponent, prevent that damage and each opponent mills that many cards.

Sol Ring

Altar of the Brood

Whenever another permanent you control enters, each opponent mills a card.

Fractured Sanity

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

Reliquary Tower

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

Aetherspouts

For each attacking creature, its owner puts it on the top or bottom of their library.

Traumatize

Target player mills half their library, rounded down.

Tasha's Hideous Laughter

Each opponent exiles cards from the top of their library until that player has exiled cards with total mana value 20 or more.

Dictate of Kruphix

Flash
At the beginning of each player's draw step, that player draws an additional card.

Terisian Mindbreaker

Whenever Terisian Mindbreaker attacks, defending player mills half their library, rounded up.
Unearth {1}{U}{U}{U} ({1}{U}{U}{U}: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the next end step or if it would leave the battlefield. Unearth only as a sorcery.)

Mana Leak

Counter target spell unless its controller pays {3}.

Tome Scour

Dispel

Island

Kami of the Crescent Moon

At the beginning of each player's draw step, that player draws an additional card.

Betrayal

Enchant creature an opponent controls
Whenever enchanted creature becomes tapped, you draw a card.

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.)

Rewind

Counter target spell. Untap up to four lands.

Dramatic Reversal

Untap all nonland permanents you control.

Fleet Swallower

Whenever Fleet Swallower attacks, target player mills half their library, rounded up.