Combat Research

Enchant creature
Enchanted creature has "Whenever this creature deals combat damage to a player, draw a card."
As long as enchanted creature is legendary, it gets +1/+1 and has ward {1}. (Whenever enchanted creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {1}.)

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.)

Treachery

Enchant creature
When Treachery enters, untap up to five lands.
You control enchanted creature.

Callaphe, Beloved of the Sea

Callaphe's power is equal to your devotion to blue. (Each {U} in the mana costs of permanents you control counts toward your devotion to blue.)
Creatures and enchantments you control have "Spells your opponents cast that target this permanent cost {1} more to cast."

Charisma

Enchant creature
Whenever enchanted creature deals damage to a creature, gain control of the other creature for as long as Charisma remains on the battlefield.

Cradle of Safety

Flash
Enchant creature you control
When Cradle of Safety enters, enchanted creature gains hexproof until end of turn. (It can't be the target of spells or abilities your opponents control.)
Enchanted creature gets +1/+1.

Enchant creature
Enchanted creature has flying and "Whenever this creature deals combat damage to a player, venture into the dungeon." (Enter the first room or advance to the next room.)

As Foretold

At the beginning of your upkeep, put a time counter on As Foretold.
Once each turn, you may pay {0} rather than pay the mana cost for a spell you cast with mana value X or less, where X is the number of time counters on As Foretold.

One with the Multiverse

You may look at the top card of your library any time.
You may play lands and cast spells from the top of your library.
Once during each of your turns, you may cast a spell from your hand or the top of your library without paying its mana cost.

Steal Artifact

Enchant artifact
You control enchanted artifact.

Island

Aqueous Form

Enchant creature
Enchanted creature can't be blocked.
Whenever enchanted creature attacks, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Copy Enchantment

You may have Copy Enchantment enter as a copy of any enchantment on the battlefield.

Fool's Demise

Enchant creature
When enchanted creature dies, return that card to the battlefield under your control.
When Fool's Demise is put into a graveyard from the battlefield, return Fool's Demise to its owner's hand.

Coastal Piracy

Whenever a creature you control deals combat damage to an opponent, you may draw a card.

Court of Cunning

When Court of Cunning enters, you become the monarch.
At the beginning of your upkeep, any number of target players each mill two cards. If you're the monarch, each of those players mills ten cards instead. (To mill a card, a player puts the top card of their library into their graveyard.)

Corrupted Conscience

Enchant creature
You control enchanted creature.
Enchanted creature has infect. (It deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

Chamber of Manipulation

Enchant land
Enchanted land has "{T}, Discard a card: Gain control of target creature until end of turn."

Frogify

Enchant creature
Enchanted creature loses all abilities and is a blue Frog creature with base power and toughness 1/1. (It loses all other card types and creature types.)

Soul Barrier

Whenever an opponent casts a creature spell, Soul Barrier deals 2 damage to that player unless they pay {2}.

Amphibian Downpour

Flash
Storm (When you cast this spell, copy it for each spell cast before it this turn. You may choose new targets for the copies. Copies become tokens.)
Enchant creature
Enchanted creature loses all abilities and is a blue Frog creature with base power and toughness 1/1.

Witness Protection

Enchant creature
Enchanted creature loses all abilities and is a green and white Citizen creature with base power and toughness 1/1 named Legitimate Businessperson. (It loses all other colors, card types, creature types, and names.)

Ichthyomorphosis

Enchant creature
Enchanted creature loses all abilities and is a blue Fish with base power and toughness 0/1.

Curious Inquiry

Enchant creature
Enchanted creature gets +1/+1 and has "Whenever this creature deals combat damage to a player, investigate." (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Curiosity

Enchant creature
Whenever enchanted creature deals damage to an opponent, you may draw a card.

Vapor Snare

Enchant creature
You control enchanted creature.
At the beginning of your upkeep, sacrifice Vapor Snare unless you return a land you control to its owner's hand.

Aether Barrier

Whenever a player casts a creature spell, that player sacrifices a permanent unless they pay {1}.

Eel Umbra

Flash (You may cast this spell any time you could cast an instant.)
Enchant creature
Enchanted creature gets +1/+1.
Umbra armor (If enchanted creature would be destroyed, instead remove all damage from it and destroy this Aura.)

Persuasion

Enchant creature (Target a creature as you cast this. This card enters attached to that creature.)
You control enchanted creature.

Ever-Watching Threshold

Whenever an opponent attacks, if they attacked you and/or a planeswalker you control, draw a card.

Infiltrator's Magemark

Enchant creature
Creatures you control that are enchanted get +1/+1 and can't be blocked except by creatures with defender.

Kitnap

Gift a card (You may promise an opponent a gift as you cast this spell. If you do, when it enters, they draw a card.)
Enchant creature
When Kitnap enters, tap enchanted creature. If the gift wasn't promised, put three stun counters on it.
You control enchanted creature.

Court of Vantress

When Court of Vantress enters, you become the monarch.
At the beginning of your upkeep, choose up to one other target enchantment or artifact. If you're the monarch, you may create a token that's a copy of it. If you're not the monarch, you may have Court of Vantress become a copy of it, except it has this ability.

Steal Enchantment

Enchant enchantment
You control enchanted enchantment.

Counterbalance

Whenever an opponent casts a spell, you may reveal the top card of your library. If you do, counter that spell if it has the same mana value as the revealed card.

Mind's Dilation

Whenever an opponent casts their first spell each turn, that player exiles the top card of their library. If it's a nonland card, you may cast it without paying its mana cost.

Legacy's Allure

At the beginning of your upkeep, you may put a treasure counter on Legacy's Allure.
Sacrifice Legacy's Allure: Gain control of target creature with power less than or equal to the number of treasure counters on Legacy's Allure. (This effect lasts indefinitely.)

Betrayal

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

Archmage Ascension

At the beginning of each end step, if you drew two or more cards this turn, you may put a quest counter on Archmage Ascension.
As long as Archmage Ascension has six or more quest counters on it, if you would draw a card, you may instead search your library for a card, put that card into your hand, then shuffle.

Threads of Disloyalty

Enchant creature with mana value 2 or less
You control enchanted creature.

Enthralling Hold

Enchant creature
You can't choose an untapped creature as this spell's target as you cast it.
You control enchanted creature.

Shark Typhoon

Whenever you cast a noncreature spell, create an X/X blue Shark creature token with flying, where X is that spell's mana value.
Cycling {X}{1}{U} ({X}{1}{U}, Discard this card: Draw a card.)
When you cycle Shark Typhoon, create an X/X blue Shark creature token with flying.

Become the Pilot

Enchant noncommander creature
You control enchanted creature.
Enchanted creature gets +2/+2 and can't be blocked unless it's attacking its owner or a permanent its owner controls.

Curse of Verbosity

Enchant player
Whenever enchanted player is attacked, you draw a card. Each opponent attacking that player does the same.

Mind Control

Enchant creature
You control enchanted creature.

Mirrormade

You may have Mirrormade enter as a copy of any artifact or enchantment on the battlefield.

Estrid's Invocation

You may have Estrid's Invocation enter as a copy of an enchantment you control, except it has "At the beginning of your upkeep, you may exile this enchantment. If you do, return it to the battlefield under its owner's control."

Invisibility

Enchant creature
Enchanted creature can't be blocked except by Walls.

Control Magic

Followed Footsteps

Enchant creature
At the beginning of your upkeep, create a token that's a copy of enchanted creature.

One with the Stars

Enchant creature or enchantment
Enchanted permanent is an enchantment and loses all other card types. (It still has its abilities, but it's no longer a creature.)

Sword Coast Sailor

Commander creatures you own have "Whenever this creature attacks a player, if no opponent has more life than that player, this creature can't be blocked this turn."

Domestication

Enchant creature
You control enchanted creature.
At the beginning of your end step, if enchanted creature's power is 4 or greater, sacrifice Domestication.

Dream Leash

Enchant permanent
You can't choose an untapped permanent as this spell's target as you cast it.
You control enchanted permanent.

Aether Storm

Creature spells can't be cast.
Pay 4 life: Destroy Aether Storm. It can't be regenerated. Any player may activate this ability.

Fealty to the Realm

Enchant creature
When Fealty to the Realm enters, you become the monarch.
The monarch controls enchanted creature.
Enchanted creature attacks each combat if able and can't attack you.

Aether Tunnel

Enchant creature
Enchanted creature gets +1/+0 and can't be blocked.

Cloak of Mists

Enchant creature
Enchanted creature can't be blocked.

Back to Basics

Nonbasic lands don't untap during their controllers' untap steps.

Abduction

Enchant creature
When Abduction enters, untap enchanted creature.
You control enchanted creature.
When enchanted creature dies, return that card to the battlefield under its owner's control.

Arcane Flight

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

Security Bypass

Enchant creature
As long as enchanted creature is attacking alone, it can't be blocked.
Enchanted creature has "Whenever this creature deals combat damage to a player, it connives." (Its controller draws a card, then discards a card. If they discarded a nonland card, they put a +1/+1 counter on this creature.)

Awesome Presence

Enchant creature
Enchanted creature can't be blocked unless defending player pays {3} for each creature they control that's blocking it.

Backfire

Enchant creature
Whenever enchanted creature deals damage to you, Backfire deals that much damage to that creature's controller.

Curse of Inertia

Enchant player
Whenever a player attacks enchanted player with one or more creatures, that attacking player may tap or untap target permanent of their choice.

Dissipation Field

Whenever a permanent deals damage to you, return it to its owner's hand.

Omniscience

You may cast spells from your hand without paying their mana costs.

Propaganda

Creatures can't attack you unless their controller pays {2} for each creature they control that's attacking you.

Overburden

Whenever a player puts a nontoken creature onto the battlefield, that player returns a land they control to its owner's hand.

Extravagant Replication

At the beginning of your upkeep, create a token that's a copy of another target nonland permanent you control.

Apathy

Enchant creature
Enchanted creature doesn't untap during its controller's untap step.
At the beginning of the upkeep of enchanted creature's controller, that player may discard a card at random. If the player does, untap that creature.

Curse of Unbinding

Enchant player
At the beginning of enchanted player's upkeep, that player reveals cards from the top of their library until they reveal a creature card. Put that card onto the battlefield under your control. That player puts the rest of the revealed cards into their graveyard.