Arvinox, the Mind Flail

Arvinox isn't a creature unless you control three or more permanents you don't own.
At the beginning of your end step, exile the bottom card of each opponent's library face down. For as long as those cards remain exiled, you may look at them, you may cast permanent spells from among them, and you may spend mana as though it were mana of any color to cast those spells.

Victor, Valgavoth's Seneschal

Eerie — Whenever an enchantment you control enters and whenever you fully unlock a Room, surveil 2 if this is the first time this ability has resolved this turn. If it's the second time, each opponent discards a card. If it's the third time, put a creature card from a graveyard onto the battlefield under your control.

Fear of Lost Teeth

When this creature dies, it deals 1 damage to any target and you gain 1 life.

Ondu Spiritdancer

Whenever an enchantment you control enters, you may create a token that's a copy of it. Do this only once each turn.

Deadly Dispute

As an additional cost to cast this spell, sacrifice an artifact or creature.
Draw two cards and create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Sun Titan

Vigilance
Whenever this creature enters or attacks, you may return target permanent card with mana value 3 or less from your graveyard to the battlefield.

Alseid of Life's Bounty

Lifelink
{1}, Sacrifice this creature: Target creature or enchantment you control gains protection from the color of your choice until end of turn.

Castle Ardenvale

This land enters tapped unless you control a Plains.
{T}: Add {W}.
{2}{W}{W}, {T}: Create a 1/1 white Human creature token.

Command Tower

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

Appendage Amalgam

Flash
Whenever this creature attacks, surveil 1. (Look at the top card of your library. You may put it into your graveyard.)

Bandit's Talent

(Gain the next level as a sorcery to add its ability.)
When this Class enters, each opponent discards two cards unless they discard a nonland card.
{B}: Level 2
At the beginning of each opponent's upkeep, if that player has one or fewer cards in hand, they lose 2 life.
{3}{B}: Level 3
At the beginning of your draw step, draw an additional card for each opponent who has one or fewer cards in hand.

Scoured Barrens

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

Revenge of Ravens

Whenever a creature attacks you or a planeswalker you control, that creature's controller loses 1 life and you gain 1 life.

Ephara's Radiance

Enchant creature
Enchanted creature has "{1}{W}, {T}: You gain 3 life."

Lurrus of the Dream-Den

Companion — Each permanent card in your starting deck has mana value 2 or less. (If this card is your chosen companion, you may put it into your hand from outside the game for {3} as a sorcery.)
Lifelink
Once during each of your turns, you may cast a permanent spell with mana value 2 or less from your graveyard.

Overlord of the Balemurk

Impending 5—{1}{B} (If you cast this spell for its impending cost, it enters with five time counters and isn't a creature until the last is removed. At the beginning of your end step, remove a time counter from it.)
Whenever this permanent enters or attacks, mill four cards, then you may return a non-Avatar creature card or a planeswalker card from your graveyard to your hand.

Auramancer

When this creature enters, you may return target enchantment card from your graveyard to your hand.

Archetype of Courage

Creatures you control have first strike.
Creatures your opponents control lose first strike and can't have or gain first strike.

Ill-Gotten Inheritance

At the beginning of your upkeep, this enchantment deals 1 damage to each opponent and you gain 1 life.
{5}{B}, Sacrifice this enchantment: It deals 4 damage to target opponent and you gain 4 life.

Thriving Moor

This land enters tapped. As it enters, choose a color other than black.
{T}: Add {B} or one mana of the chosen color.

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.

Lionheart Glimmer

Ward {2} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {2}.)
Whenever you attack, creatures you control get +1/+1 until end of turn.

Fate Unraveler

Whenever an opponent draws a card, this creature deals 1 damage to that player.

Mesa Enchantress

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

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.

Shineshadow Snarl

As this land enters, you may reveal a Plains or Swamp card from your hand. If you don't, this land enters tapped.
{T}: Add {W} or {B}.

Athreos, Shroud-Veiled

Indestructible
As long as your devotion to white and black is less than seven, Athreos isn't a creature.
At the beginning of your end step, put a coin counter on another target creature.
Whenever a creature with a coin counter on it dies or is put into exile, return that card to the battlefield under your control.

Nightmare Shepherd

Flying
Whenever another nontoken creature you control dies, you may exile it. If you do, create a token that's a copy of that creature, except it's 1/1 and it's a Nightmare in addition to its other types.

Soul Snare

{W}, Sacrifice this enchantment: Exile target creature that's attacking you or a planeswalker you control.

Gray Merchant of Asphodel

When this creature enters, each opponent loses X life, where X is your devotion to black. You gain life equal to the life lost this way. (Each {B} in the mana costs of permanents you control counts toward your devotion to black.)

Daxos, Blessed by the Sun

Daxos's toughness is equal to your devotion to white. (Each {W} in the mana costs of permanents you control counts toward your devotion to white.)
Whenever another creature you control enters or dies, you gain 1 life.

Master of the Feast

Flying
At the beginning of your upkeep, each opponent draws a card.

Soulreaper of Mogis

{2}{B}, Sacrifice a creature: Draw a card.

Redress Fate

Return all artifact and enchantment cards from your graveyard to the battlefield.
Miracle {3}{W} (You may cast this card for its miracle cost when you draw it if it's the first card you drew this turn.)

Moon-Blessed Cleric

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

Seal of Cleansing

Sacrifice this enchantment: Destroy target artifact or enchantment.

Journey to Nowhere

When this enchantment enters, exile target creature.
When this enchantment leaves the battlefield, return the exiled card to the battlefield under its owner's control.

Life Insurance

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.)
Whenever a nontoken creature dies, you lose 1 life and create a Treasure token.

Erebos, Bleak-Hearted

Indestructible
As long as your devotion to black is less than five, Erebos isn't a creature.
Whenever another creature you control dies, you may pay 2 life. If you do, draw a card.
{1}{B}, Sacrifice another creature: Target creature gets -2/-1 until end of turn.

Evolving Wilds

{T}, Sacrifice this land: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Feed the Swarm

Destroy target creature or enchantment an opponent controls. You lose life equal to that permanent's mana value.

Martial Impetus

Enchant creature
Enchanted creature gets +1/+1 and is goaded. (It attacks each combat if able and attacks a player other than you if able.)
Whenever enchanted creature attacks, each other creature that's attacking one of your opponents gets +1/+1 until end of turn.

Doomwake Giant

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

Tymaret, Chosen from Death

Tymaret's toughness is equal to your devotion to black. (Each {B} in the mana costs of permanents you control counts toward your devotion to black.)
{1}{B}: Exile up to two target cards from graveyards. You gain 1 life for each creature card exiled this way.

Katilda's Rising Dawn

Enchant creature
Enchanted creature has flying, lifelink, and protection from Vampires, and it gets +X/+X, where X is the number of permanents you control that are Spirits and/or enchantments.
If Katilda's Rising Dawn would be put into a graveyard from anywhere, exile it instead.

Katilda, Dawnhart Martyr

Flying, lifelink, protection from Vampires
Katilda's power and toughness are each equal to the number of permanents you control that are Spirits and/or enchantments.
Disturb {3}{W}{W} (You may cast this card from your graveyard transformed for its disturb cost.)

Katilda, Dawnhart Martyr // Katilda's Rising Dawn

Shroudstomper

Deathtouch
Whenever this creature enters or attacks, each opponent loses 2 life. You gain 2 life and draw a card.

Insatiable Avarice

Spree (Choose one or more additional costs.)
+ {2} — Search your library for a card, then shuffle and put that card on top.
+ {B}{B} — Target player draws three cards and loses 3 life.

Hospital Room

Whenever you attack, put a +1/+1 counter on target attacking 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.)

Surgical Suite

When you unlock this door, return target creature card with mana value 3 or less from your graveyard to the battlefield.
(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.)

Surgical Suite // Hospital Room

Heliod, God of the Sun

Indestructible
As long as your devotion to white is less than five, Heliod isn't a creature. (Each {W} in the mana costs of permanents you control counts toward your devotion to white.)
Other creatures you control have vigilance.
{2}{W}{W}: Create a 2/1 white Cleric enchantment creature token.

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

Monologue Tax

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

Duelist's Heritage

Whenever one or more creatures attack, you may have target attacking creature gain double strike until end of turn.

Smothering Tithe

Whenever an opponent draws a card, that player may pay {2}. If the player doesn't, you create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Grasp of Fate

When this enchantment enters, for each opponent, exile up to one target nonland permanent that player controls until this enchantment leaves the battlefield. (Those permanents return under their owners' control.)

Spear of Heliod

Creatures you control get +1/+1.
{1}{W}{W}, {T}: Destroy target creature that dealt damage to you this turn.

Painful Quandary

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

Terramorphic Expanse

Redemption Arc

Enchant creature
Enchanted creature has indestructible and is goaded. (It attacks each combat if able and attacks a player other than you if able.)
{1}{W}: Exile enchanted creature.

Fear of the Dark

Whenever this creature attacks, if defending player controls no Glimmer creatures, it gains menace and deathtouch until end of turn. (A creature with menace can't be blocked except by two or more creatures.)

Phyrexian Arena

At the beginning of your upkeep, you draw a card and you lose 1 life.

Kaya's Ghostform

Enchant creature or planeswalker you control
When enchanted permanent dies or is put into exile, return that card to the battlefield under your control.

All That Glitters

Enchant creature
Enchanted creature gets +1/+1 for each artifact and/or enchantment you control.

Vow of Duty

Enchant creature
Enchanted creature gets +2/+2, has vigilance, and can't attack you or planeswalkers you control.

Sevinne's Reclamation

Return target permanent card with mana value 3 or less from your graveyard to the battlefield. If this spell was cast from a graveyard, you may copy this spell and may choose a new target for the copy.
Flashback {4}{W} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Smuggler's Share

At the beginning of each end step, draw a card for each opponent who drew two or more cards this turn, then create a Treasure token for each opponent who had two or more lands enter the battlefield under their control this turn.

Access Maze

Once during each of your turns, you may cast a spell from your hand by paying life equal to its mana value rather than paying its mana cost.
(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.)

Cramped Vents

When you unlock this door, this Room deals 6 damage to target creature an opponent controls. You gain life equal to the excess damage dealt this way.
(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.)

Cramped Vents // Access Maze

Dark Ritual

Night's Whisper

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.

Plains

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.