Solve the Equation

Search your library for an instant or sorcery card, reveal it, put it into your hand, then shuffle.

Drown in Dreams

Choose one. If you control a commander as you cast this spell, you may choose both instead.
• Target player draws X cards.
• Target player mills twice X cards.

Cephalid Illusionist

Whenever Cephalid Illusionist becomes the target of a spell or ability, mill three cards.
{2}{U}, {T}: Prevent all combat damage that would be dealt to and dealt by target creature you control this turn.

Thassa's Oracle

When Thassa's Oracle enters, look at the top X cards of your library, where X is your devotion to blue. Put up to one of them on top of your library and the rest on the bottom of your library in a random order. If X is greater than or equal to the number of cards in your library, you win the game. (Each {U} in the mana costs of permanents you control counts toward your devotion to blue.)

Grolnok, the Omnivore

Whenever a Frog you control attacks, mill three cards.
Whenever a permanent card is put into your graveyard from your library, exile it with a croak counter on it.
You may play lands and cast spells from among cards you own in exile with croak counters on them.

Mental Note

Worldly Tutor

Search your library for a creature card, reveal it, then shuffle and put the card on top.

Windfall

Each player discards their hand, then draws cards equal to the greatest number of cards a player discarded this way.

Long-Term Plans

Search your library for a card, then shuffle and put that card third from the top.

Mesmeric Orb

Whenever a permanent becomes untapped, that permanent's controller mills a card.

Dakra Mystic

{U}, {T}: Each player reveals the top card of their library. You may put the revealed cards into their owners' graveyards. If you don't, each player draws a card.

Hedron Crab

Landfall — Whenever a land you control enters, target player mills three cards.

Hermit Druid

{G}, {T}: Reveal cards from the top of your library until you reveal a basic land card. Put that card into your hand and all other cards revealed this way into your graveyard.

Traumatize

Target player mills half their library, rounded down.

Consider

Surveil 1. (Look at the top card of your library. You may put it into your graveyard.)
Draw a card.

Winds of Rebuke

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

Mystical Tutor

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

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.