Mystic Remora

Cumulative upkeep {1} (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)
Whenever an opponent casts a noncreature spell, you may draw a card unless that player pays {4}.

Baleful Strix

Flying, deathtouch
When Baleful Strix enters, draw a card.

Etali, Primal Storm

Whenever Etali, Primal Storm attacks, exile the top card of each player's library, then you may cast any number of spells from among those cards without paying their mana costs.

Chromatic Lantern

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

Izzet Signet

Treasure Nabber

Whenever an opponent taps an artifact for mana, gain control of that artifact until the end of your next turn.

Cascade Bluffs

{T}: Add {C}.
{U/R}, {T}: Add {U}{U}, {U}{R}, or {R}{R}.

Graven Cairns

{T}: Add {C}.
{B/R}, {T}: Add {B}{B}, {B}{R}, or {R}{R}.

Bedevil

Destroy target artifact, creature, or planeswalker.

Counterspell

Stolen Strategy

At the beginning of your upkeep, exile the top card of each opponent's library. Until end of turn, you may cast spells from among those exiled cards, and you may spend mana as though it were mana of any color to cast those spells.

Nicol Bolas, Planeswalker

+3: Destroy target noncreature permanent.
−2: Gain control of target creature.
−9: Nicol Bolas, Planeswalker deals 7 damage to target player or planeswalker. That player or that planeswalker's controller discards seven cards, then sacrifices seven permanents.

Deliver Unto Evil

Choose up to four target cards in your graveyard. If you control a Bolas planeswalker, return those cards to your hand. Otherwise, an opponent chooses two of them. Leave the chosen cards in your graveyard and put the rest into your hand.
Exile Deliver Unto Evil.

Toxic Deluge

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

Shivan Reef

{T}: Add {C}.
{T}: Add {U} or {R}. Shivan Reef deals 1 damage to you.

Chaos Warp

The owner of target permanent shuffles it into their library, then reveals the top card of their library. If it's a permanent card, they put it onto the battlefield.

Animate Dead

Enchant creature card in a graveyard
When Animate Dead enters, if it's on the battlefield, it loses "enchant creature card in a graveyard" and gains "enchant creature put onto the battlefield with Animate Dead." Return enchanted creature card to the battlefield under your control and attach Animate Dead to it. When Animate Dead leaves the battlefield, that creature's controller sacrifices it.
Enchanted creature gets -1/-0.

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.

The Eldest Reborn

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Each opponent sacrifices a creature or planeswalker.
II — Each opponent discards a card.
III — Put target creature or planeswalker card from a graveyard onto the battlefield under your control.

Praetor's Grasp

Search target opponent's library for a card and exile it face down. Then that player shuffles. You may play that card for as long as it remains exiled.

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.

Luxury Suite

Luxury Suite enters tapped unless you have two or more opponents.
{T}: Add {B} or {R}.

Slave of Bolas

Gain control of target creature. Untap that creature. It gains haste until end of turn. Sacrifice it at the beginning of the next end step.

Dragonskull Summit

Dragonskull Summit enters tapped unless you control a Swamp or a Mountain.
{T}: Add {B} or {R}.

Nightscape Familiar

Blue spells and red spells you cast cost {1} less to cast.
{1}{B}: Regenerate Nightscape Familiar.

Arcane Signet

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

Morphic Pool

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

Bribery

Search target opponent's library for a creature card and put that card onto the battlefield under your control. Then that player shuffles.

Crumbling Necropolis

Crumbling Necropolis enters tapped.
{T}: Add {U}, {B}, or {R}.

Sol Ring

Geyadrone Dihada

Protection from permanents with corruption counters on them
+1: Each opponent loses 2 life and you gain 2 life. Put a corruption counter on up to one other target creature or planeswalker.
−3: Gain control of target creature or planeswalker until end of turn. Untap it and put a corruption counter on it. It gains haste until end of turn.
−7: Gain control of each permanent with a corruption counter on it.

Phyrexian Arena

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

Nicol Bolas, God-Pharaoh

+2: Target opponent exiles cards from the top of their library until they exile a nonland card. Until end of turn, you may cast that card without paying its mana cost.
+1: Each opponent exiles two cards from their hand.
−4: Nicol Bolas, God-Pharaoh deals 7 damage to target opponent, creature an opponent controls, or planeswalker an opponent controls.
−12: Exile each nonland permanent your opponents control.

Agent of Treachery

When Agent of Treachery enters, gain control of target permanent.
At the beginning of your end step, if you control three or more permanents you don't own, draw three cards.

Scalding Tarn

{T}, Pay 1 life, Sacrifice Scalding Tarn: Search your library for an Island or Mountain card, put it onto the battlefield, then shuffle.

Steam Vents

({T}: Add {U} or {R}.)
As Steam Vents enters, you may pay 2 life. If you don't, it enters tapped.

Blatant Thievery

For each opponent, gain control of target permanent that player controls.

Mass Manipulation

Gain control of X target creatures and/or planeswalkers.

Mountain

Cruel Ultimatum

Target opponent sacrifices a creature, discards three cards, then loses 5 life. You return a creature card from your graveyard to your hand, draw three cards, then gain 5 life.

Notion Thief

Flash
If an opponent would draw a card except the first one they draw in each of their draw steps, instead that player skips that draw and you draw a card.

Polluted Delta

{T}, Pay 1 life, Sacrifice Polluted Delta: Search your library for an Island or Swamp card, put it onto the battlefield, then shuffle.

Narset's Reversal

Copy target instant or sorcery spell, then return it to its owner's hand. You may choose new targets for the copy.

Dragonlord Silumgar

Flying, deathtouch
When Dragonlord Silumgar enters, gain control of target creature or planeswalker for as long as you control Dragonlord Silumgar.

Dimir Signet

Underground River

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

Swamp

Damnation

Destroy all creatures. They can't be regenerated.

Watery Grave

({T}: Add {U} or {B}.)
As Watery Grave enters, you may pay 2 life. If you don't, it enters tapped.

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.

Thought Vessel

You have no maximum hand size.
{T}: Add {C}.

Hellkite Tyrant

Flying, trample
Whenever Hellkite Tyrant deals combat damage to a player, gain control of all artifacts that player controls.
At the beginning of your upkeep, if you control twenty or more artifacts, you win the game.

Crux of Fate

Choose one —
• Destroy all Dragon creatures.
• Destroy all non-Dragon creatures.

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.

Nicol Bolas, Dragon-God

Nicol Bolas, Dragon-God has all loyalty abilities of all other planeswalkers on the battlefield.
+1: You draw a card. Each opponent exiles a card from their hand or a permanent they control.
−3: Destroy target creature or planeswalker.
−8: Each opponent who doesn't control a legendary creature or planeswalker loses the game.

Training Center

Training Center enters tapped unless you have two or more opponents.
{T}: Add {U} or {R}.

Fallen Shinobi

Ninjutsu {2}{U}{B} ({2}{U}{B}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
Whenever Fallen Shinobi deals combat damage to a player, that player exiles the top two cards of their library. Until end of turn, you may play those cards without paying their mana costs.

Lightning Greaves

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.)
Equip {0}

Nicol Bolas, the Arisen

+2: Draw two cards.
−3: Nicol Bolas, the Arisen deals 10 damage to target creature or planeswalker.
−4: Put target creature or planeswalker card from a graveyard onto the battlefield under your control.
−12: Exile all but the bottom card of target player's library.

Nicol Bolas, the Ravager

Flying
When Nicol Bolas, the Ravager enters, each opponent discards a card.
{4}{U}{B}{R}: Exile Nicol Bolas, the Ravager, then return him to the battlefield transformed under his owner's control. Activate only as a sorcery.

Nicol Bolas, the Ravager // Nicol Bolas, the Arisen

Dominus of Fealty

Flying
At the beginning of your upkeep, you may gain control of target permanent until end of turn. If you do, untap it and it gains haste until end of turn.

Drowned Catacomb

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

Expropriate

Council's dilemma — Starting with you, each player votes for time or money. For each time vote, take an extra turn after this one. For each money vote, choose a permanent owned by the voter and gain control of it. Exile Expropriate.

Island

Bolas's Citadel

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. If you cast a spell this way, pay life equal to its mana value rather than pay its mana cost.
{T}, Sacrifice ten nonland permanents: Each opponent loses 10 life.

Torment of Hailfire

Repeat the following process X times. Each opponent loses 3 life unless that player sacrifices a nonland permanent or discards a card.

Exotic Orchard

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

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.

Rhystic Study

Whenever an opponent casts a spell, you may draw a card unless that player pays {1}.

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.

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.")

Sulfur Falls

Sulfur Falls enters tapped unless you control an Island or a Mountain.
{T}: Add {U} or {R}.

Rakdos Signet

Sulfurous Springs

{T}: Add {C}.
{T}: Add {B} or {R}. Sulfurous Springs deals 1 damage to you.

Dack Fayden

+1: Target player draws two cards, then discards two cards.
−2: Gain control of target artifact.
−6: You get an emblem with "Whenever you cast a spell that targets one or more permanents, gain control of those permanents."

Bloodstained Mire

{T}, Pay 1 life, Sacrifice Bloodstained Mire: Search your library for a Swamp or Mountain card, put it onto the battlefield, then shuffle.

Blood Crypt

({T}: Add {B} or {R}.)
As Blood Crypt enters, you may pay 2 life. If you don't, it enters tapped.

In Bolas's Clutches

Enchant permanent
You control enchanted permanent.
Enchanted permanent is legendary.

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.