Consider

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

Path to Exile

Exile target creature. Its controller may search their library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Elesh Norn, Grand Cenobite

Vigilance
Other creatures you control get +2/+2.
Creatures your opponents control get -2/-2.

Unburial Rites

Return target creature card from your graveyard to the battlefield.
Flashback {3}{W} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Mana Tithe

Counter target spell unless its controller pays {1}.

Avacyn, Angel of Hope

Flying, vigilance, indestructible
Other permanents you control have indestructible.

Balance

Each player chooses a number of lands they control equal to the number of lands controlled by the player who controls the fewest, then sacrifices the rest. Players discard cards and sacrifice creatures the same way.

Fatal Push

Destroy target creature if it has mana value 2 or less.
Revolt — Destroy that creature if it has mana value 4 or less instead if a permanent you controlled left the battlefield this turn.

Unmarked Grave

Search your library for a nonlegendary card, put that card into your graveyard, then shuffle.

Trial of Ambition

When Trial of Ambition enters, target opponent sacrifices a creature of their choice.
When a Cartouche you control enters, return Trial of Ambition to its owner's hand.

Duress

Target opponent reveals their hand. You choose a noncreature, nonland card from it. That player discards that card.

Jin-Gitaxias, Core Augur

Flash
At the beginning of your end step, draw seven cards.
Each opponent's maximum hand size is reduced by seven.

Oath of Liliana

When Oath of Liliana enters, each opponent sacrifices a creature of their choice.
At the beginning of each end step, if a planeswalker entered the battlefield under your control this turn, create a 2/2 black Zombie creature token.

Griselbrand

Flying, lifelink
Pay 7 life: Draw seven cards.

Daze

You may return an Island you control to its owner's hand rather than pay this spell's mana cost.
Counter target spell unless its controller pays {1}.

Animate Dead

Enchant creature card in a graveyard
When Animate Dead enters, if it's on the battlefield, it loses "enchant creature card in a graveyard" and gains "enchant creature put onto the battlefield with Animate Dead." Return enchanted creature card to the battlefield under your control and attach Animate Dead to it. When Animate Dead leaves the battlefield, that creature's controller sacrifices it.
Enchanted creature gets -1/-0.

Liliana of the Veil

+1: Each player discards a card.
−2: Target player sacrifices a creature.
−6: Separate all permanents target player controls into two piles. That player sacrifices all permanents in the pile of their choice.

Spellseeker

When Spellseeker enters, you may search your library for an instant or sorcery card with mana value 2 or less, reveal it, put it into your hand, then shuffle.

Sheoldred, Whispering One

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)
At the beginning of your upkeep, return target creature card from your graveyard to the battlefield.
At the beginning of each opponent's upkeep, that player sacrifices a creature of their choice.

Dance of the Dead

Enchant creature card in a graveyard
When Dance of the Dead enters, if it's on the battlefield, it loses "enchant creature card in a graveyard" and gains "enchant creature put onto the battlefield with Dance of the Dead." Put enchanted creature card onto the battlefield tapped under your control and attach Dance of the Dead to it. When Dance of the Dead leaves the battlefield, that creature's controller sacrifices it.
Enchanted creature gets +1/+1 and doesn't untap during its controller's untap step.
At the beginning of the upkeep of enchanted creature's controller, that player may pay {1}{B}. If the player does, untap that creature.

Mana Leak

Counter target spell unless its controller pays {3}.

Reanimate

Put target creature card from a graveyard onto the battlefield under your control. You lose life equal to its mana value.

Thoughtseize

Target player reveals their hand. You choose a nonland card from it. That player discards that card. You lose 2 life.

Vile Entomber

Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)
When this creature enters, search your library for a card, put that card into your graveyard, then shuffle.

Swords to Plowshares

Exile target creature. Its controller gains life equal to its power.

Mental Misstep

({U/P} can be paid with either {U} or 2 life.)
Counter target spell with mana value 1.

Rune-Scarred Demon

Flying
When this creature enters, search your library for a card, put it into your hand, then shuffle.

Ashen Rider

Flying
When Ashen Rider enters or dies, exile target permanent.

Magister of Worth

Flying
Will of the council — When Magister of Worth enters, starting with you, each player votes for grace or condemnation. If grace gets more votes, each player returns each creature card from their graveyard to the battlefield. If condemnation gets more votes or the vote is tied, destroy all creatures other than Magister of Worth.

Spell Snare

Collective Brutality

Escalate—Discard a card. (Pay this cost for each mode chosen beyond the first.)
Choose one or more —
• Target opponent reveals their hand. You choose an instant or sorcery card from it. That player discards that card.
• Target creature gets -2/-2 until end of turn.
• Target opponent loses 2 life and you gain 2 life.

Demonic Tutor

Search your library for a card, put that card into your hand, then shuffle.

Baleful Strix

Flying, deathtouch
When Baleful Strix enters, draw a card.

Counterspell

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.)

Inquisition of Kozilek

Target player reveals their hand. You choose a nonland card from it with mana value 3 or less. That player discards that card.

Spell Pierce

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

Hoarding Broodlord

Convoke
Flying
When Hoarding Broodlord enters, search your library for a card, exile it face down, then shuffle. For as long as that card remains exiled, you may play it.
Spells you cast from exile have convoke.

Iona, Shield of Emeria

Flying
As Iona, Shield of Emeria enters, choose a color.
Your opponents can't cast spells of the chosen color.

Buried Alive

Search your library for up to three creature cards, put them into your graveyard, then shuffle.

Ponder

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

Brainstorm

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

Aminatou, the Fateshifter

+1: Draw a card, then put a card from your hand on top of your library.
−1: Exile another target permanent you own, then return it to the battlefield under your control.
−6: Choose left or right. Each player gains control of all nonland permanents other than Aminatou, the Fateshifter controlled by the next player in the chosen direction.
Aminatou, the Fateshifter can be your commander.