Have

Szadek, Lord of Secrets

Flying
If Szadek, Lord of Secrets would deal combat damage to a player, instead put that many +1/+1 counters on Szadek and that player mills that many cards.

Traumatize

Target player mills half their library, rounded down.

Circu, Dimir Lobotomist

Whenever you cast a blue spell, exile the top card of target player's library.
Whenever you cast a black spell, exile the top card of target player's library.
Your opponents can't cast spells with the same name as a card exiled with Circu, Dimir Lobotomist.

Dark Ritual

Swamp

Balustrade Spy

Flying
When Balustrade Spy enters, target player reveals cards from the top of their library until they reveal a land card, then puts those cards into their graveyard.

Ruin Crab

Landfall — Whenever a land you control enters, each opponent mills three cards. (To mill a card, a player puts the top card of their library into their graveyard.)

Island

Ghostly Flicker

Exile two target artifacts, creatures, and/or lands you control, then return those cards to the battlefield under your control.

Tome Scour

Raven Guild Master

Whenever Raven Guild Master deals combat damage to a player, that player exiles the top ten cards of their library.
Morph {2}{U}{U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Navigator's Ruin

Raid — At the beginning of your end step, if you attacked this turn, target opponent mills four cards.

Painful Quandary

Whenever an opponent casts a spell, that player loses 5 life unless they discard a card.

Psychic Corrosion

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

Jace's Erasure

Whenever you draw a card, you may have target player mill a card.

Consult the Necrosages

Choose one —
• Target player draws two cards.
• Target player discards two cards.

Crafty Pathmage

{T}: Target creature with power 2 or less can't be blocked this turn.

Wall of Lost Thoughts

Defender (This creature can't attack.)
When Wall of Lost Thoughts enters, target player mills four cards. (They put the top four cards of their library into their graveyard.)

Sage's Row Denizen

Whenever another blue creature you control enters, target player mills two cards.

Consuming Aberration

Consuming Aberration's power and toughness are each equal to the number of cards in your opponents' graveyards.
Whenever you cast a spell, each opponent reveals cards from the top of their library until they reveal a land card, then puts those cards into their graveyard.

Snow-Covered Swamp

Mirror Mockery

Enchant creature
Whenever enchanted creature attacks, you may create a token that's a copy of that creature. Exile that token at end of combat.

Fleet Swallower

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

Paranoid Delusions

Target player mills three cards.
Cipher (Then you may exile this spell card encoded on a creature you control. Whenever that creature deals combat damage to a player, its controller may cast a copy of the encoded card without paying its mana cost.)

Duskmantle, House of Shadow

{T}: Add {C}.
{U}{B}, {T}: Target player mills a card.

Venture Deeper

Target player mills four cards. (Then exile this card. You may cast the creature later from exile.)

Merfolk Secretkeeper

Merfolk Secretkeeper // Venture Deeper

Whispersilk Cloak

Equipped creature can't be blocked and has shroud. (It can't be the target of spells or abilities.)
Equip {2}

Oona, Queen of the Fae

Flying
{X}{U/B}: Choose a color. Target opponent exiles the top X cards of their library. For each card of the chosen color exiled this way, create a 1/1 blue and black Faerie Rogue creature token with flying.

Dimir Aqueduct

Dimir Aqueduct enters tapped.
When Dimir Aqueduct enters, return a land you control to its owner's hand.
{T}: Add {U}{B}.

Tourach, Dread Cantor

Kicker {B}{B} (You may pay an additional {B}{B} as you cast this spell.)
Protection from white
Whenever an opponent discards a card, put a +1/+1 counter on Tourach, Dread Cantor.
When Tourach enters, if it was kicked, target opponent discards two cards at random.

Fell Specter

Flying
When Fell Specter enters, target opponent discards a card.
Whenever an opponent discards a card, that player loses 2 life.

Dimir Cutpurse

Whenever Dimir Cutpurse deals combat damage to a player, that player discards a card and you draw a card.

Train of Thought

Replicate {1}{U} (When you cast this spell, copy it for each time you paid its replicate cost.)
Draw a card.