Hostage Taker

When Hostage Taker enters, exile another target creature or artifact until Hostage Taker leaves the battlefield. You may cast that card for as long as it remains exiled, and mana of any type can be spent to cast that spell.

Counterspell

Author of Shadows

When Author of Shadows enters, exile all opponents' graveyards. Choose a nonland card exiled this way. You may cast that card for as long as it remains exiled, and you may spend mana as though it were mana of any color to cast that spell.

Deathcap Glade

Deathcap Glade enters tapped unless you control two or more other lands.
{T}: Add {B} or {G}.

Rogue Class

(Gain the next level as a sorcery to add its ability.)
Whenever a creature you control deals combat damage to a player, exile the top card of that player's library face down. You may look at it for as long as it remains exiled.
{1}{U}{B}: Level 2
Creatures you control have menace.
{2}{U}{B}: Level 3
You may play cards exiled with Rogue Class, and you may spend mana as though it were mana of any color to cast those spells.

Dead Man's Chest

Enchant creature an opponent controls
When enchanted creature dies, exile cards equal to its power from the top of its owner's library. You may cast spells from among those cards for as long as they remain exiled, and mana of any type can be spent to cast them.

Entish Restoration

Sacrifice a land. Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle. If you control a creature with power 4 or greater, instead search your library for up to three basic land cards, put them onto the battlefield tapped, then shuffle.

Arvinox, the Mind Flail

Arvinox, the Mind Flail 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.

Gonti, Lord of Luxury

Deathtouch
When Gonti, Lord of Luxury enters, look at the top four cards of target opponent's library, exile one of them face down, then put the rest on the bottom of that library in a random order. You may cast that card for as long as it remains exiled, and mana of any type can be spent to cast that spell.

Chromatic Lantern

Lands you control have "{T}: Add one mana of any color."
{T}: Add one mana of any color.

Cyclonic Rift

Return target nonland permanent you don't control to its owner's hand.
Overload {6}{U} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Morphic Pool

Morphic Pool enters tapped unless you have two or more opponents.
{T}: Add {U} or {B}.

Thief of Sanity

Flying
Whenever Thief of Sanity deals combat damage to a player, look at the top three cards of that player's library, exile one of them face down, then put the rest into their graveyard. You may cast that card for as long as it remains exiled, and mana of any type can be spent to cast that spell.

Drowned Catacomb

Drowned Catacomb enters tapped unless you control an Island or a Swamp.
{T}: Add {U} or {B}.

Blightwing Bandit

Flying, deathtouch
Whenever you cast your first spell during each opponent's turn, look at the top card of that player's library, then exile it face down. You may play that card for as long as it remains exiled, and mana of any type can be spent to cast it.

Opulent Palace

Opulent Palace enters tapped.
{T}: Add {B}, {G}, or {U}.

Lullmage's Domination

This spell costs {3} less to cast if it targets a creature whose controller has eight or more cards in their graveyard.
Gain control of target creature with mana value X.

Tidechannel Pathway

Barkchannel Pathway

Barkchannel Pathway // Tidechannel Pathway

Replicating Ring

{T}: Add one mana of any color.
At the beginning of your upkeep, put a night counter on Replicating Ring. Then if it has eight or more night counters on it, remove all of them and create eight colorless snow artifact tokens named Replicated Ring with "{T}: Add one mana of any color."

Sol Ring

Forest

Saw It Coming

Counter target spell.
Foretell {1}{U} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Hero's Downfall

Thada Adel, Acquisitor

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)
Whenever Thada Adel, Acquisitor deals combat damage to a player, search that player's library for an artifact card and exile it. Then that player shuffles. Until end of turn, you may play that card.

Fiend of the Shadows

Flying
Whenever Fiend of the Shadows deals combat damage to a player, that player exiles a card from their hand. You may play that card for as long as it remains exiled.
Sacrifice a Human: Regenerate Fiend of the Shadows.

Covetous Urge

Target opponent reveals their hand. You choose a nonland card from that player's graveyard or hand and exile it. You may cast that card for as long as it remains exiled, and you may spend mana as though it were mana of any color to cast that spell.

Xanathar, Guild Kingpin

At the beginning of your upkeep, choose target opponent. Until end of turn, that player can't cast spells, you may look at the top card of their library any time, you may play the top card of their library, and you may spend mana as though it were mana of any color to cast spells this way.

Swamp

Three Visits

Search your library for a Forest card, put it onto the battlefield, then shuffle.

Havengul Lich

{1}: You may cast target creature card in a graveyard this turn. When you cast it this turn, Havengul Lich gains all activated abilities of that card until end of turn.

Poison the Cup

Destroy target creature. If this spell was foretold, scry 2.
Foretell {1}{B} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Ponder

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

Hedron Archive

{T}: Add {C}{C}.
{2}, {T}, Sacrifice Hedron Archive: Draw two cards.

Opposition Agent

Flash
You control your opponents while they're searching their libraries.
While an opponent is searching their library, they exile each card they find. You may play those cards for as long as they remain exiled, and you may spend mana as though it were mana of any color to cast them.

Arcane Signet

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

Mnemonic Betrayal

Exile all opponents' graveyards. You may cast spells from among those cards this turn, and mana of any type can be spent to cast them. At the beginning of the next end step, if any of those cards remain exiled, return them to their owners' graveyards.
Exile Mnemonic Betrayal.

Cultivate

Search your library for up to two basic land cards, reveal those cards, put one onto the battlefield tapped and the other into your hand, then shuffle.

Mind Stone

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

Intellect Devourer

Devour Intellect — When Intellect Devourer enters, each opponent exiles a card from their hand until Intellect Devourer leaves the battlefield.
Body Thief — You may play lands and cast spells from among cards exiled with Intellect Devourer. If you cast a spell this way, you may spend mana as though it were mana of any color to cast it.

Dreamroot Cascade

Dreamroot Cascade enters tapped unless you control two or more other lands.
{T}: Add {G} or {U}.

Gríma, Saruman's Footman

Gríma, Saruman's Footman can't be blocked.
Whenever Gríma deals combat damage to a player, that player exiles cards from the top of their library until they exile an instant or sorcery card. You may cast that card without paying its mana cost. Then that player puts the exiled cards that weren't cast this way on the bottom of their library in a random order.

Elder Brain

Menace
Whenever Elder Brain attacks a player, exile all cards from that player's hand, then they draw that many cards. You may play lands and cast spells from among the exiled cards for as long as they remain exiled. If you cast a spell this way, you may spend mana as though it were mana of any color to cast it.

Enter the Unknown

Target creature you control explores. (Reveal the top card of your library. Put that card into your hand if it's a land. Otherwise, put a +1/+1 counter on the creature, then put the card back or put it into your graveyard.)
You may play an additional land this turn.

Cunning Rhetoric

Whenever an opponent attacks you and/or one or more planeswalkers you control, exile the top card of that player's library. You may play that card for as long as it remains exiled, and you may spend mana as though it were mana of any color to cast it.

Command Tower

Draugr Necromancer

If a nontoken creature an opponent controls would die, exile that card with an ice counter on it instead.
You may cast spells from among cards in exile your opponents own with ice counters on them, and you may spend mana from snow sources as though it were mana of any color to cast those spells.

Siphon Insight

Look at the top two cards of target opponent's library. Exile one of them face down and put the other on the bottom of that library. You may play the exiled card for as long as it remains exiled, and you may spend mana as though it were mana of any color to cast that spell.
Flashback {1}{U}{B}

Rampant Growth

Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Gilded Lotus

Malakir Mire

Malakir Mire enters tapped.
{T}: Add {B}.

Malakir Rebirth

Choose target creature. You lose 2 life. Until end of turn, that creature gains "When this creature dies, return it to the battlefield tapped under its owner's control."

Malakir Rebirth // Malakir Mire

Slither Blade

Changeling Outcast

Changeling (This card is every creature type.)
Changeling Outcast can't block and can't be blocked.

Kheru Mind-Eater

Menace
Whenever Kheru Mind-Eater deals combat damage to a player, that player exiles a card from their hand face down.
You may look at cards exiled with Kheru Mind-Eater, and you may play lands and cast spells from among those cards.

Memory Deluge

Look at the top X cards of your library, where X is the amount of mana spent to cast this spell. Put two of them into your hand and the rest on the bottom of your library in a random order.
Flashback {5}{U}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Path to the Festival

Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle. Then if there are three or more basic land types among lands you control, scry 1. (Look at the top card of your library. You may put that card on the bottom.)
Flashback {4}{G} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Mind Flayer

Dominate Monster — When Mind Flayer enters, gain control of target creature for as long as you control Mind Flayer.

Branch of Boseiju

Reach
Branch of Boseiju gets +1/+1 for each land you control.

Boseiju Reaches Skyward

(As this Saga enters and after your draw step, add a lore counter.)
I — Search your library for up to two basic Forest cards, reveal them, put them into your hand, then shuffle.
II — Put up to one target land card from your graveyard on top of your library.
III — Exile this Saga, then return it to the battlefield transformed under your control.

Boseiju Reaches Skyward // Branch of Boseiju

Gonti, Canny Acquisitor

Spells you cast but don't own cost {1} less to cast.
Whenever one or more creatures you control deal combat damage to a player, look at the top card of that player's library, then exile it face down. You may play that card for as long as it remains exiled, and mana of any type can be spent to cast that spell.

Murkwater Pathway

Clearwater Pathway

Clearwater Pathway // Murkwater Pathway

Hinterland Harbor

Hinterland Harbor enters tapped unless you control a Forest or an Island.
{T}: Add {G} or {U}.

Slitherbore Pathway

Darkbore Pathway

Darkbore Pathway // Slitherbore Pathway

Quandrix Cultivator

When Quandrix Cultivator enters, you may search your library for a basic Forest or Island card, put it onto the battlefield, then shuffle.

Hedonist's Trove

When Hedonist's Trove enters, exile target opponent's graveyard.
You may play lands from among cards exiled with Hedonist's Trove.
You may cast spells from among cards exiled with Hedonist's Trove. You can't cast more than one spell this way each turn.

Psychic Intrusion

Shipwreck Marsh

Shipwreck Marsh enters tapped unless you control two or more other lands.
{T}: Add {U} or {B}.

Villainous Wealth

Target opponent exiles the top X cards of their library. You may cast any number of spells with mana value X or less from among them without paying their mana costs.

Mind Spring

Grow from the Ashes

Kicker {2} (You may pay an additional {2} as you cast this spell.)
Search your library for a basic land card, put it onto the battlefield, then shuffle. If this spell was kicked, instead search your library for two basic land cards, put them onto the battlefield, then shuffle.

Brainstealer Dragon

Flying
At the beginning of your end step, exile the top card of each opponent's library. You may play those cards for as long as they remain exiled. If you cast a spell this way, you may spend mana as though it were mana of any color to cast it.
Whenever a nonland permanent an opponent owns enters the battlefield under your control, they lose life equal to its mana value.

Maralen of the Mornsong

Players can't draw cards.
At the beginning of each player's draw step, that player loses 3 life, searches their library for a card, puts it into their hand, then shuffles.

Island

Tempted by the Oriq

For each opponent, gain control of up to one target creature or planeswalker that player controls with mana value 3 or less.

Circuitous Route

Search your library for up to two basic land cards and/or Gate cards, put them onto the battlefield tapped, then shuffle.

Chromatic Orrery

You may spend mana as though it were mana of any color.
{T}: Add {C}{C}{C}{C}{C}.
{5}, {T}: Draw a card for each color among permanents you control.