Consider

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

Have

Sigil of the Empty Throne

Whenever you cast an enchantment spell, create a 4/4 white Angel creature token with flying.

Island

Doomwake Giant

Constellation — Whenever Doomwake Giant or another enchantment you control enters, creatures your opponents control get -1/-1 until end of turn.

Enduring Curiosity

Flash
Whenever a creature you control deals combat damage to a player, draw a card.
When Enduring Curiosity dies, if it was a creature, return it to the battlefield under its owner's control. It's an enchantment. (It's not a creature.)

Extravagant Replication

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

Terminus

Put all creatures on the bottom of their owners' libraries.
Miracle {W} (You may cast this card for its miracle cost when you draw it if it's the first card you drew this turn.)

Sol Ring

Portent

Look at the top three cards of target player's library, then put them back in any order. You may have that player shuffle.
Draw a card at the beginning of the next turn's upkeep.

Archon of Sun's Grace

Flying
Lifelink (Damage dealt by this creature also causes you to gain that much life.)
Pegasus creatures you control have lifelink.
Constellation — Whenever an enchantment you control enters, create a 2/2 white Pegasus creature token with flying.

Underground River

{T}: Add {C}.
{T}: Add {U} or {B}. Underground River deals 1 damage to you.

Otherworldly Gaze

Surveil 3. (Look at the top three cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)
Flashback {1}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Dusty Parlor

Whenever you cast an enchantment spell, put a number of +1/+1 counters equal to that spell's mana value on up to one target creature.
(You may cast either half. That door unlocks on the battlefield. As a sorcery, you may pay the mana cost of a locked door to unlock it.)

Secret Arcade

Nonland permanents you control and permanent spells you control are enchantments in addition to their other types.
(You may cast either half. That door unlocks on the battlefield. As a sorcery, you may pay the mana cost of a locked door to unlock it.)

Secret Arcade // Dusty Parlor

Swamp

Telling Time

Look at the top three cards of your library. Put one of those cards into your hand, one on top of your library, and one on the bottom of your library.

Temple of Enlightenment

This land enters tapped.
When this land enters, scry 1. (Look at the top card of your library. You may put that card on the bottom.)
{T}: Add {W} or {U}.

Soaring Lightbringer

Flying
Other enchantment creatures you control have flying.
Whenever you attack a player, create a 1/1 white Glimmer enchantment creature token that's tapped and attacking that player.

Plains

Bident of Thassa

Whenever a creature you control deals combat damage to a player, you may draw a card.
{1}{U}, {T}: Creatures your opponents control attack this turn if able.

Isolated Chapel

Isolated Chapel enters tapped unless you control a Plains or a Swamp.
{T}: Add {W} or {B}.

Demon of Fate's Design

Flying, trample
Once during each of your turns, you may cast an enchantment spell by paying life equal to its mana value rather than paying its mana cost.
{2}{B}, Sacrifice another enchantment: Demon of Fate's Design gets +X/+0 until end of turn, where X is the sacrificed enchantment's mana value.

Propaganda

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

Tainted Field

{T}: Add {C}.
{T}: Add {W} or {B}. Activate only if you control a Swamp.

Imprisoned in the Moon

Enchant creature, land, or planeswalker
Enchanted permanent is a colorless land with "{T}: Add {C}" and loses all other card types and abilities.

Exotic Orchard

{T}: Add one mana of any color that a land an opponent controls could produce.

Time Wipe

Return a creature you control to its owner's hand, then destroy all creatures.

Halimar Depths

Halimar Depths enters tapped.
When Halimar Depths enters, look at the top three cards of your library, then put them back in any order.
{T}: Add {U}.

Mesa Enchantress

Whenever you cast an enchantment spell, you may draw a card.

Inkshield

Prevent all combat damage that would be dealt to you this turn. For each 1 damage prevented this way, create a 2/1 white and black Inkling creature token with flying.

Anguished Unmaking

Exile target nonland permanent. You lose 3 life.

Temple of Deceit

This land enters tapped.
When this land enters, scry 1. (Look at the top card of your library. You may put that card on the bottom.)
{T}: Add {U} or {B}.

Zur the Enchanter

Flying
Whenever Zur the Enchanter attacks, you may search your library for an enchantment card with mana value 3 or less, put it onto the battlefield, then shuffle.

Ash Barrens

{T}: Add {C}.
Basic landcycling {1} ({1}, Discard this card: Search your library for a basic land card, reveal it, put it into your hand, then shuffle.)

Ethereal Absolution

Creatures you control get +1/+1.
Creatures your opponents control get -1/-1.
{2}{W}{B}: Exile target card from an opponent's graveyard. If it was a creature card, you create a 1/1 white and black Spirit creature token with flying.

Toxic Deluge

As an additional cost to cast this spell, pay X life.
All creatures get -X/-X until end of turn.

Bojuka Bog

Bojuka Bog enters tapped.
When Bojuka Bog enters, exile target player's graveyard.
{T}: Add {B}.

Caves of Koilos

{T}: Add {C}.
{T}: Add {W} or {B}. Caves of Koilos deals 1 damage to you.

Zur, Eternal Schemer

Flying
Enchantment creatures you control have deathtouch, lifelink, and hexproof.
{1}{W}: Target non-Aura enchantment you control becomes a creature in addition to its other types and has base power and base toughness each equal to its mana value.

Ponder

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

Blind Obedience

Extort (Whenever you cast a spell, you may pay {W/B}. If you do, each opponent loses 1 life and you gain that much life.)
Artifacts and creatures your opponents control enter tapped.

Timely Ward

You may cast Timely Ward as though it had flash if it targets a commander.
Enchant creature
Enchanted creature has indestructible.

Copy Enchantment

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

Temple of Silence

This land enters tapped.
When this land enters, scry 1. (Look at the top card of your library. You may put that card on the bottom.)
{T}: Add {W} or {B}.

Moon-Blessed Cleric

Divine Intervention — When Moon-Blessed Cleric enters, you may search your library for an enchantment card, reveal it, then shuffle and put that card on top.

Arcane Signet

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

Penance

Put a card from your hand on top of your library: The next time a black or red source of your choice would deal damage this turn, prevent that damage.

Tranquil Cove

This land enters tapped.
When this land enters, you gain 1 life.
{T}: Add {W} or {U}.

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.)

Swords to Plowshares

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

Starnheim Courser

Flying
Artifact and enchantment spells you cast cost {1} less to cast.

Swan Song

Counter target enchantment, instant, or sorcery spell. Its controller creates a 2/2 blue Bird creature token with flying.

Starfield Mystic

Enchantment spells you cast cost {1} less to cast.
Whenever an enchantment you control is put into a graveyard from the battlefield, put a +1/+1 counter on Starfield Mystic.

Arcane Sanctum

Arcane Sanctum enters tapped.
{T}: Add {W}, {U}, or {B}.

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.

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.

Aminatou, Veil Piercer

At the beginning of your upkeep, 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.)
Each enchantment card in your hand has miracle. Its miracle cost is equal to its mana cost reduced by {4}. (You may cast a card for its miracle cost when you draw it if it's the first card you drew this turn.)

Azorius Chancery

Azorius Chancery enters tapped.
When Azorius Chancery enters, return a land you control to its owner's hand.
{T}: Add {W}{U}.

Fear of Sleep Paralysis

Flying
Eerie — Whenever Fear of Sleep Paralysis or another enchantment you control enters and whenever you fully unlock a Room, tap up to one target creature and put a stun counter on it.
Stun counters can't be removed from permanents your opponents control. (They won't untap if they have stun counters.)

Adarkar Wastes

{T}: Add {C}.
{T}: Add {W} or {U}. Adarkar Wastes deals 1 damage to you.

Cast Out

Flash
When Cast Out enters, exile target nonland permanent an opponent controls until Cast Out leaves the battlefield.
Cycling {W} ({W}, Discard this card: Draw a card.)

Oblivion Ring

When Oblivion Ring enters, exile another target nonland permanent.
When Oblivion Ring leaves the battlefield, return the exiled card to the battlefield under its owner's control.

Talisman of Progress

{T}: Add {C}.
{T}: Add {W} or {U}. Talisman of Progress deals 1 damage to you.

Sphere of Safety

Creatures can't attack you or planeswalkers you control unless their controller pays {X} for each of those creatures, where X is the number of enchantments you control.

Monologue Tax

Whenever an opponent casts their second spell each turn, you create a Treasure token.

Brainstorm

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

Shadow of the Second Sun

Enchant player
At the beginning of each of enchanted player's postcombat main phases, there is an additional beginning phase after this phase. (The end step happens after the added untap, upkeep, and draw steps.)

Cacophony Unleashed

When Cacophony Unleashed enters, if you cast it, destroy all nonenchantment creatures.
Whenever Cacophony Unleashed or another enchantment you control enters, until end of turn, Cacophony Unleashed becomes a legendary 6/6 Nightmare God creature with menace and deathtouch. It's still an enchantment.

Refute

Counter target spell. Draw a card, then discard a card.

Tainted Isle

{T}: Add {C}.
{T}: Add {U} or {B}. Activate only if you control a Swamp.

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice Mind Stone: 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.

Command Tower

Mirrormade

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

Entity Tracker

Flash
Eerie — Whenever an enchantment you control enters and whenever you fully unlock a Room, draw a card.

Glacial Fortress

Glacial Fortress enters tapped unless you control a Plains or an Island.
{T}: Add {W} or {U}.

Planar Disruption

Enchant artifact, creature, or planeswalker
Enchanted permanent can't attack or block, and its activated abilities can't be activated.

Hall of Heliod's Generosity

{T}: Add {C}.
{1}{W}, {T}: Put target enchantment card from your graveyard on top of your library.

Starfield of Nyx

At the beginning of your upkeep, you may return target enchantment card from your graveyard to the battlefield.
As long as you control five or more enchantments, each other non-Aura enchantment you control is a creature in addition to its other types and has base power and base toughness each equal to its mana value.

Scry 1. (Look at the top card of your library. You may put that card on the bottom.)
Draw a card.

Obscura Storefront

When Obscura Storefront enters, sacrifice it. When you do, search your library for a basic Plains, Island, or Swamp card, put it onto the battlefield tapped, then shuffle and you gain 1 life.

Locker Room

Whenever one or more creatures you control deal combat damage to a player, draw a card.
(You may cast either half. That door unlocks on the battlefield. As a sorcery, you may pay the mana cost of a locked door to unlock it.)

Bottomless Pool

When you unlock this door, return up to one target creature to its owner's hand.
(You may cast either half. That door unlocks on the battlefield. As a sorcery, you may pay the mana cost of a locked door to unlock it.)

Bottomless Pool // Locker Room

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.

Inquisitive Glimmer

Enchantment spells you cast cost {1} less to cast.
Unlock costs you pay cost {1} less.

Commander's Sphere

{T}: Add one mana of any color in your commander's color identity.
Sacrifice Commander's Sphere: Draw a card.