The Master of Keys

Flying
When The Master of Keys enters, put X +1/+1 counters on it and mill twice X cards.
Each enchantment card in your graveyard has escape. The escape cost is equal to the card's mana cost plus exile three other cards from your graveyard. (You may cast cards from your graveyard for their escape cost.)

Perpetual Timepiece

{T}: Mill two cards.
{2}, Exile this artifact: Shuffle any number of target cards from your graveyard into your library.

Gremlin Tamer

Eerie — Whenever an enchantment you control enters and whenever you fully unlock a Room, create a 1/1 red Gremlin creature token.

Forlorn Flats

This land enters tapped.
When this land enters, it deals 1 damage to target opponent.
{T}: Add {W} or {B}.

Trapped in the Screen

Ward {2} (Whenever this enchantment becomes the target of a spell or ability an opponent controls, counter it unless that player pays {2}.)
When this enchantment enters, exile target artifact, creature, or enchantment an opponent controls until this enchantment leaves the battlefield.

Tocasia's Welcome

Whenever one or more creatures you control with mana value 3 or less enter, draw a card. This ability triggers only once each turn.

Murder Investigation

Enchant creature you control
When enchanted creature dies, create X 1/1 white Soldier creature tokens, where X is its power.

Swamp

Thriving Heath

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

Killian, Ink Duelist

Lifelink
Menace (This creature can't be blocked except by two or more creatures.)
Spells you cast that target a creature cost {2} less to cast.

Portent of Calamity

Reveal the top X cards of your library. For each card type, you may exile a card of that type from among them. Put the rest into your graveyard. You may cast a spell from among the exiled cards without paying its mana cost if you exiled four or more cards this way. Then put the rest of the exiled cards into your hand.

Fall of the First Civilization

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — You and target opponent each draw two cards.
II — Exile target artifact an opponent controls.
III — Each player chooses three nonland permanents they control. Destroy all other nonland permanents.

Eriette of the Charmed Apple

Each creature that's enchanted by an Aura you control can't attack you or planeswalkers you control.
At the beginning of your end step, each opponent loses X life and you gain X life, where X is the number of Auras you control.

Dismal Backwater

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

Seal of Cleansing

Sacrifice this enchantment: Destroy target artifact or enchantment.

Inquisitive Glimmer

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

Plains

Psemilla, Meletian Poet

Whenever you cast your first enchantment spell each turn, create a 2/2 white Nymph enchantment creature token.
At the beginning of each combat, if you control five or more enchantments, Psemilla gets +4/+4 and gains lifelink until end of turn. (Damage dealt by this creature also causes you to gain that much life.)

Gremlin

Forsaken Sanctuary

This land enters tapped.
{T}: Add {W} or {B}.

Tranquil Cove

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

Mortify

Stargaze

Look at twice X cards from the top of your library. Put X cards from among them into your hand and the rest into your graveyard. You lose X life.

Murky Sewer

This land enters tapped unless a player has 13 or less life.
{T}: Add {U} or {B}.

Karametra's Blessing

Target creature gets +2/+2 until end of turn. If it's an enchanted creature or enchantment creature, it also gains hexproof and indestructible until end of turn. (It can't be the target of spells or abilities your opponents control. Damage and effects that say "destroy" don't destroy it.)

Blighted Agent

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
This creature can't be blocked.

Minimus Containment

Enchant nonland permanent
Enchanted permanent is a Treasure artifact with "{T}, Sacrifice this artifact: Add one mana of any color," and it loses all other abilities. (If it was a creature, it's no longer a creature.)

Robot

Another Chance

You may mill two cards. Then return up to two creature cards from your graveyard to your hand. (To mill two cards, put the top two cards of your library into your graveyard.)

Skybridge Towers

This land enters tapped.
{T}: Add {W} or {U}.
{2}{W}{U}, {T}, Sacrifice this land: Draw a card.

Soul Tithe

Enchant nonland permanent
At the beginning of the upkeep of enchanted permanent's controller, that player sacrifices it unless they pay {X}, where X is its mana value.

Ethereal Armor

Enchant creature
Enchanted creature gets +1/+1 for each enchantment you control and has first strike.

Staggering Insight

Enchant creature
Enchanted creature gets +1/+1 and has lifelink and "Whenever this creature deals combat damage to a player, draw a card."

Submerged Boneyard

This land enters tapped.
{T}: Add {U} or {B}.

Sheltered by Ghosts

Enchant creature you control
When this Aura enters, exile target nonland permanent an opponent controls until this Aura leaves the battlefield.
Enchanted creature gets +1/+0 and has lifelink and ward {2}.

Reality Shift

Exile target creature. Its controller manifests the top card of their library. (That player puts the top card of their library onto the battlefield face down as a 2/2 creature. If it's a creature card, it can be turned face up any time for its mana cost.)

Ascent of the Worthy

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I, II — Choose a creature you control. Until your next turn, all damage that would be dealt to creatures you control is dealt to that creature instead.
III — Return target creature card from your graveyard to the battlefield with a flying counter on it. That creature is an Angel Warrior in addition to its other types.

Skullsnap Nuisance

Flying
Eerie — Whenever an enchantment you control enters and whenever you fully unlock a Room, surveil 1. (Look at the top card of your library. You may put it into your graveyard.)

Silent Hallcreeper

This creature can't be blocked.
Whenever this creature deals combat damage to a player, choose one that hasn't been chosen —
• Put two +1/+1 counters on this creature.
• Draw a card.
• This creature becomes a copy of another target creature you control.

Neglected Manor

This land enters tapped unless a player has 13 or less life.
{T}: Add {W} or {B}.

Manifest

(You can cover a face-down manifested creature with this reminder card.
A manifested creature card can be turned face up any time for its mana cost. A face-down card can also be turned face up for its morph cost.)

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.)

Valgavoth's Lair

Hexproof
This land enters tapped. As it enters, choose a color.
{T}: Add one mana of the chosen color.

Treno, Dark City

Transcendent Envoy

Flying
Aura spells you cast cost {1} less to cast.

Soldier

Island

Appendage Amalgam

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

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.

Valgavoth's Faithful

{3}{B}, Sacrifice this creature: Return target creature card from your graveyard to the battlefield. Activate only as a sorcery.