Have

Constrictor Sage

When this creature enters, tap target creature an opponent controls and put a stun counter on it. (If a permanent with a stun counter would become untapped, remove one from it instead.)
Renew — {2}{U}, Exile this card from your graveyard: Tap target creature an opponent controls and put a stun counter on it. Activate only as a sorcery.

Get Out

Choose one —
• Counter target creature or enchantment spell.
• Return one or two target creatures and/or enchantments you own to your hand.

The Warring Triad

Flying, trample, haste
As long as there are fewer than eight cards in your graveyard, The Warring Triad isn't a creature.
{T}, Mill a card: Target player adds one mana of any color.

Getting

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.)

Bender's Waterskin

Untap this artifact during each other player's untap step.
{T}: Add one mana of any color.

Sea God's Revenge

Return up to three target creatures your opponents control to their owners' hands. Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

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.

Ichor Synthesizer

Whenever you cast a noncreature spell, put an oil counter on this creature.
As long as this creature has four or more oil counters on it, it gets +2/+0 and can't be blocked.

Dreadwaters

Target player mills X cards, where X is the number of lands you control.

Arcane Signet

{T}: Add one mana of any color in your commander's color identity.

Fogwalker

Skulk (This creature can't be blocked by creatures with greater power.)
When this creature enters, target creature an opponent controls doesn't untap during its controller's next untap step.

Stern Scolding

Counter target creature spell with power or toughness 2 or less.

Proft's Eidetic Memory

When Proft's Eidetic Memory enters, draw a card.
You have no maximum hand size.
At the beginning of combat on your turn, if you've drawn more than one card this turn, put X +1/+1 counters on target creature you control, where X is the number of cards you've drawn this turn minus one.

Dissolve

Counter target spell. Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Brainstorm

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

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.)

Unwind

Counter target noncreature spell. Untap up to three lands.

Fireshrieker

Equipped creature has double strike. (It deals both first-strike and regular combat damage.)
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

Crippling Chill

Tap target creature. It doesn't untap during its controller's next untap step.
Draw a card.

Spell Snare

Arcane Flight

Enchant creature
Enchanted creature gets +1/+1 and has flying.

Watery Grasp

Enchant creature
Enchanted creature doesn't untap during its controller's untap step.
Waterbend {5}: Enchanted creature's owner shuffles it into their library. (While paying a waterbend cost, you can tap your artifacts and creatures to help. Each one pays for {1}.)

Mesmerizing Dose

Enchant creature
When this Aura enters, tap enchanted creature, then proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)
Enchanted creature doesn't untap during its controller's untap step.

Snowmelt Stag

Vigilance
During your turn, this creature has base power and toughness 5/2.
{5}{U}{U}: This creature can't be blocked this turn.

Rakshasa's Disdain

Counter target spell unless its controller pays {1} for each card in your graveyard.

Fresh Start

Flash
Enchant creature
Enchanted creature gets -5/-0 and loses all abilities.

Syncopate

Counter target spell unless its controller pays {X}. If that spell is countered this way, exile it instead of putting it into its owner's graveyard.

Island

Watcher of the Wayside

When this creature enters, target player mills two cards. You gain 2 life. (To mill two cards, a player puts the top two cards of their library into their graveyard.)

Curator's Ward

Enchant permanent
Enchanted permanent has hexproof.
When enchanted permanent leaves the battlefield, if it was historic, draw two cards. (Artifacts, legendaries, and Sagas are historic.)

Floodpits Drowner

Flash
Vigilance
When this creature enters, tap target creature an opponent controls and put a stun counter on it.
{1}{U}, {T}: Shuffle this creature and target creature with a stun counter on it into their owners' libraries.

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}

Fleet Swallower

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

Gridlock

Lulu, Stern Guardian

Whenever an opponent attacks you, choose target creature attacking you. Put a stun counter on that creature.
{3}{U}: Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Riverwalk Technique

Choose one —
• The owner of target nonland permanent puts it on their choice of the top or bottom of their library.
• Counter target noncreature spell.

Clash of Wills

Counter target spell unless its controller pays {X}.

Otter-Penguin

Whenever you draw your second card each turn, this creature gets +1/+2 until end of turn and can't be blocked this turn.

Honest Work

Enchant creature an opponent controls
When this Aura enters, tap enchanted creature and remove all counters from it.
Enchanted creature loses all abilities and is a Citizen with base power and toughness 1/1 and "{T}: Add {C}" named Humble Merchant. (It loses all other creature types and names.)

Clammy Prowler

Whenever this creature attacks, another target attacking creature can't be blocked this turn.

Disperse

Return target nonland permanent to its owner's hand.

Duskmourn's Domination

Enchant creature
You control enchanted creature.
Enchanted creature gets -3/-0 and loses all abilities.

Sol Ring

Unable to Scream

Enchant creature
Enchanted creature loses all abilities and is a Toy artifact creature with base power and toughness 0/2 in addition to its other types.
As long as enchanted creature is face down, it can't be turned face up.

Flare of Denial

You may sacrifice a nontoken blue creature rather than pay this spell's mana cost.
Counter target spell.

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.)

Coralhelm Guide

{4}{U}: Target creature can't be blocked this turn.

Ringing Strike Mastery

Enchant creature
When this Aura enters, tap enchanted creature.
Enchanted creature doesn't untap during its controller's untap step.
Enchanted creature has "{5}: Untap this creature."

Annul

Counter target artifact or enchantment spell.

Vodalian Arcanist

{T}: Add {C}. Spend this mana only to cast an instant or sorcery spell.

Giant Koi

Waterbend {3}: This creature can't be blocked this turn. (While paying a waterbend cost, you can tap your artifacts and creatures to help. Each one pays for {1}.)
Islandcycling {2} ({2}, Discard this card: Search your library for an Island card, reveal it, put it into your hand, then shuffle.)

Unsummon

Return target creature to its owner's hand.

Don't Make a Sound

Counter target spell unless its controller pays {2}. If they do, surveil 2. (Look at the top two cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)

Nullify

Rhystic Study

Whenever an opponent casts a spell, you may draw a card unless that player pays {1}.

Relic Runner

This creature can't be blocked if you've cast a historic spell this turn. (Artifacts, legendaries, and Sagas are historic.)

Amazing Acrobatics

Choose one or both —
• Counter target spell.
• Tap one or two target creatures.

Harbinger of the Seas

Rescue

Return target permanent you control to its owner's hand.

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.

Ghost Vacuum

{T}: Exile target card from a graveyard.
{6}, {T}, Sacrifice this artifact: Put each creature card exiled with this artifact onto the battlefield under your control with a flying counter on it. Each of them is a 1/1 Spirit in addition to its other types. Activate only as a sorcery.

Fraying Sanity

Enchant player
At the beginning of each end step, enchanted player mills X cards, where X is the number of cards put into their graveyard from anywhere this turn.

Twist Reality

Choose one —
• Counter target spell.
• Manifest dread. (Look at the top two cards of your library. Put one onto the battlefield face down as a 2/2 creature and the other into your graveyard. Turn it face up any time for its mana cost if it's a creature card.)