Valgavoth's Onslaught

Manifest dread X times, then put X +1/+1 counters on each of those creatures. (To manifest dread, look at the top two cards of your library, then 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.)

Syr Konrad, the Grim

Whenever another creature dies, or a creature card is put into a graveyard from anywhere other than the battlefield, or a creature card leaves your graveyard, Syr Konrad, the Grim deals 1 damage to each opponent.
{1}{B}: Each player mills a card. (They each put the top card of their library into their graveyard.)

Withering Torment

Destroy target creature or enchantment. You lose 2 life.

Doppelgang

For each of X target permanents, create X tokens that are copies of that permanent.

Forest

Commune with Evil

Look at the top four cards of your library. Put one of them into your hand and the rest into your graveyard. You gain 3 life.

Unwilling Vessel

Vigilance
Eerie — Whenever an enchantment you control enters and whenever you fully unlock a Room, put a possession counter on Unwilling Vessel.
When Unwilling Vessel dies, create an X/X blue Spirit creature token with flying, where X is the number of counters on Unwilling Vessel.

Rope

Equipped creature gets +1/+2, has reach, and can't be blocked by more than one creature.
{2}, Sacrifice Rope: Draw a card.
Equip {3}

Growing Dread

Flash
When Growing Dread enters, 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.)
Whenever you turn a permanent face up, put a +1/+1 counter on it.

Fractured Realm

If a triggered ability of a permanent you control triggers, that ability triggers an additional time.
(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.)

Have

Mirror Room

When you unlock this door, create a token that's a copy of target creature you control, except it's a Reflection in addition to its other creature 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.)

Mirror Room // Fractured Realm

Drowned Diner

When you unlock this door, draw three cards, then discard 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.)

Meat Locker

When you unlock this door, tap up to one target creature and put two stun counters on it. (If a permanent with a stun counter would become untapped, remove one from it instead.)
(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.)

Meat Locker // Drowned Diner

Vengeful Creeper

Disguise {5}{G} (You may cast this card face down for {3} as a 2/2 creature with ward {2}. Turn it face up any time for its disguise cost.)
When Vengeful Creeper is turned face up, destroy target artifact or enchantment an opponent controls.

Weight Room

When you unlock this door, manifest dread, then put three +1/+1 counters on that 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.)

Moldering Gym

When you unlock this door, search your library for a basic land card, put it onto the battlefield tapped, then shuffle.
(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.)

Moldering Gym // Weight Room

Horrid Vigor

Target creature gains deathtouch and indestructible until end of turn.

Oasis Gardener

When Oasis Gardener enters, you gain 2 life.
{T}: Add one mana of any color.

Hauntwoods Shrieker

Whenever Hauntwoods Shrieker attacks, 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.)
{1}{G}: Reveal target face-down permanent. If it's a creature card, you may turn it face up.

Eternal Witness

When Eternal Witness enters, you may return target card from your graveyard to your hand.

Vile Mutilator

As an additional cost to cast this spell, sacrifice a creature or enchantment.
Flying, trample
When Vile Mutilator enters, each opponent sacrifices a nontoken enchantment of their choice, then sacrifices a nontoken creature of their choice.

Vorosh, the Hunter

Flying
Whenever Vorosh, the Hunter deals combat damage to a player, you may pay {2}{G}. If you do, put six +1/+1 counters on Vorosh.

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.)

Pilfered Plans

Target player mills two cards. Draw two cards.

Commander's Sphere

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

Snakeskin Veil

Put a +1/+1 counter on target creature you control. It gains hexproof until end of turn. (It can't be the target of spells or abilities your opponents control.)

Cautious Survivor

Survival — At the beginning of your second main phase, if Cautious Survivor is tapped, you gain 2 life.

Island

Fear of Lost Teeth

When Fear of Lost Teeth dies, it deals 1 damage to any target and you gain 1 life.

Long Goodbye

This spell can't be countered. (This includes by the ward ability.)
Destroy target creature or planeswalker with mana value 3 or less.

Malevolent Chandelier

Flying
{2}: Put target card from a graveyard on the bottom of its owner's library. Activate only as a sorcery.

Swamp

Quick-Draw Katana

During your turn, equipped creature gets +2/+0 and has first strike. (It deals combat damage before creatures without first strike.)
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

Bashful Beastie

When Bashful Beastie dies, 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.)

Macabre Reconstruction

This spell costs {2} less to cast if a creature card was put into your graveyard from anywhere this turn.
Return up to two target creature cards from your graveyard to your hand.

Macabre Waltz

Return up to two target creature cards from your graveyard to your hand, then discard a card.

Blooming Marsh

Blooming Marsh enters tapped unless you control two or fewer other lands.
{T}: Add {B} or {G}.

Sol Ring

Sterling Hound

When Sterling Hound enters, 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.)

Seasons Past

Return any number of cards with different mana values from your graveyard to your hand. Put Seasons Past on the bottom of its owner's library.

Oblivious Bookworm

At the beginning of your end step, you may draw a card. If you do, discard a card unless a permanent entered the battlefield face down under your control this turn or you turned a permanent face up this turn.

Unauthorized Exit

Return target nonland permanent to its owner's hand. Surveil 1. (Look at the top card of your library. You may put it into your graveyard.)

Rakish Scoundrel

Deathtouch
When Rakish Scoundrel enters or is turned face up, target creature gains indestructible until end of turn.
Disguise {4}{B/G}{B/G} (You may cast this card face down for {3} as a 2/2 creature with ward {2}. Turn it face up any time for its disguise cost.)

Daggermaw Megalodon

Vigilance
Islandcycling {2} ({2}, Discard this card: Search your library for an Island card, reveal it, put it into your hand, then shuffle.)