Have

Consuming Aberration

Consuming Aberration's power and toughness are each equal to the number of cards in your opponents' graveyards.
Whenever you cast a spell, each opponent reveals cards from the top of their library until they reveal a land card, then puts those cards into their graveyard.

Canyon Slough

({T}: Add {B} or {R}.)
This land enters tapped.
Cycling {2} ({2}, Discard this card: Draw a card.)

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.

Commander's Sphere

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

Sulfur Falls

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

Defile

Target creature gets -1/-1 until end of turn for each Swamp you control.

Immersturm Skullcairn

This land enters tapped.
{T}: Add {B}.
{1}{B}{R}{R}, {T}, Sacrifice this land: It deals 3 damage to target player. That player discards a card. Activate only as a sorcery.

Arcane Signet

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

Mountain

Death Tyrant

Menace
Negative Energy Cone — Whenever an attacking creature you control or a blocking creature an opponent controls dies, create a 2/2 black Zombie creature token.
{5}{B}: Return this card from your graveyard to the battlefield tapped.

The Great Work

(As this Saga enters and after your draw step, add a lore counter.)
I — This Saga deals 3 damage to target opponent and each creature they control.
II — Create three Treasure tokens.
III — Until end of turn, you may cast instant and sorcery spells from any graveyard. If a spell cast this way would be put into a graveyard, exile it instead. Exile this Saga, then return it to the battlefield (front face up).

Urabrask

First strike
Whenever you cast an instant or sorcery spell, Urabrask deals 1 damage to target opponent. Add {R}.
{R}: Exile Urabrask, then return it to the battlefield transformed under its owner's control. Activate only as a sorcery and only if you've cast three or more instant and/or sorcery spells this turn.

Urabrask // The Great Work

Overwhelming Forces

Destroy all creatures target opponent controls. Draw a card for each creature destroyed this way.

Marchesa, Dealer of Death

Whenever you commit a crime, you may pay {1}. If you do, look at the top two cards of your library. Put one of them into your hand and the other into your graveyard. (Targeting opponents, anything they control, and/or cards in their graveyards is a crime.)

Hive of the Eye Tyrant

If you control two or more other lands, this land enters tapped.
{T}: Add {B}.
{3}{B}: Until end of turn, this land becomes a 3/3 black Beholder creature with menace and "Whenever this creature attacks, exile target card from defending player's graveyard." It's still a land.

Fevered Suspicion

Each opponent exiles cards from the top of their library until they exile a nonland card. You may cast any number of spells from among those nonland cards without paying their mana costs.
Rebound (If you cast this spell from your hand, exile it as it resolves. At the beginning of your next upkeep, you may cast this card from exile without paying its mana cost.)

Exterminator Magmarch

Whenever you cast an instant or sorcery spell that targets only a single nonland permanent an opponent controls, if another opponent controls one or more nonland permanents that spell could target, choose one of those permanents. Copy that spell. The copy targets the chosen permanent.
{1}{B}: Regenerate this creature.

Snuff Out

If you control a Swamp, you may pay 4 life rather than pay this spell's mana cost.
Destroy target nonblack creature. It can't be regenerated.

Blue Sun's Twilight

Gain control of target creature with mana value X or less. If X is 5 or more, create a token that's a copy of that creature.

Stifle

Counter target activated or triggered ability. (Mana abilities can't be targeted.)

Stormcatch Mentor

Haste
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Instant and sorcery spells you cast cost {1} less to cast.

Wizards of Thay

Myriad (Whenever this creature attacks, for each opponent other than defending player, you may create a token copy that's tapped and attacking that player or a planeswalker they control. Exile the tokens at end of combat.)
Instant and sorcery spells you cast cost {1} less to cast.
You may cast sorcery spells as though they had flash.

Bonfire of the Damned

Bonfire of the Damned deals X damage to target player or planeswalker and each creature that player or that planeswalker's controller controls.
Miracle {X}{R} (You may cast this card for its miracle cost when you draw it if it's the first card you drew this turn.)

Sunbird Effigy

Flying, vigilance, haste
Sunbird Effigy's power and toughness are each equal to the number of colors among the exiled cards used to craft it.
{T}: For each color among the exiled cards used to craft this creature, add one mana of that color.

Sunbird Standard

{T}: Add one mana of any color.
Craft with one or more {5} ({5}, Exile this artifact, Exile one or more other permanents you control and/or cards from your graveyard: Return this card transformed under its owner's control. Craft only as a sorcery.)

Sunbird Standard // Sunbird Effigy

Nicol Bolas, Dragon-God

Nicol Bolas 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.

Seething Landscape

{T}: Add {C}.
{T}, Sacrifice this land: Search your library for a basic Island, Swamp, or Mountain card, put it onto the battlefield tapped, then shuffle.
Cycling {U}{B}{R} ({U}{B}{R}, Discard this card: Draw a card.)

Leechridden Swamp

({T}: Add {B}.)
This land enters tapped.
{B}, {T}: Each opponent loses 1 life. Activate only if you control two or more black permanents.

Lier, Disciple of the Drowned

Spells can't be countered.
Each instant and sorcery card in your graveyard has flashback. The flashback cost is equal to that card's mana cost.

Fling

As an additional cost to cast this spell, sacrifice a creature.
Fling deals damage equal to the sacrificed creature's power to any target.

Blood Money

Destroy all creatures. For each nontoken creature destroyed this way, you create a tapped Treasure token.

Maestros Theater

When this land enters, sacrifice it. When you do, search your library for a basic Island, Swamp, or Mountain card, put it onto the battlefield tapped, then shuffle and you gain 1 life.

Deadly Rollick

If you control a commander, you may cast this spell without paying its mana cost.
Exile target creature.

Acquire

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

Xander's Lounge

({T}: Add {U}, {B}, or {R}.)
This land enters tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)

Ghastly Death Tyrant

When this creature enters, choose one —
• Disintegration Ray — Destroy target enchantment an opponent controls. You lose life equal to its mana value.
• Death Ray — Creatures you control gain deathtouch until end of turn.

Temple of the False God

{T}: Add {C}{C}. Activate only if you control five or more lands.

Fire Covenant

As an additional cost to cast this spell, pay X life.
Fire Covenant deals X damage divided as you choose among any number of target creatures.

Vodalian Arcanist

{T}: Add {C}. Spend this mana only to cast an instant or sorcery spell.

Zevlor, Elturel Exile

Haste
{2}, {T}: When you next cast an instant or sorcery spell that targets only a single opponent or a single permanent an opponent controls this turn, for each other opponent, choose that player or a permanent they control, copy that spell, and the copy targets the chosen player or permanent.

Inundated Archive

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

Waterlogged Teachings

Search your library for an instant card or a card with flash, reveal it, put it into your hand, then shuffle.

Waterlogged Teachings // Inundated Archive

Crumbling Necropolis

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

Minamo, School at Water's Edge

{T}: Add {U}.
{U}, {T}: Untap target legendary permanent.

Death Kiss

Whenever a creature an opponent controls attacks one of your opponents, double its power until end of turn.
{X}{X}{R}: Monstrosity X. (If this creature isn't monstrous, put X +1/+1 counters on it and it becomes monstrous.)
When this creature becomes monstrous, goad up to X target creatures your opponents control.

Command Tower

Sunken Hollow

({T}: Add {U} or {B}.)
This land enters tapped unless you control two or more basic lands.

Fetid Pools

({T}: Add {U} or {B}.)
This land enters tapped.
Cycling {2} ({2}, Discard this card: Draw a card.)

Delay

Counter target spell. If the spell is countered this way, exile it with three time counters on it instead of putting it into its owner's graveyard. If it doesn't have suspend, it gains suspend. (At the beginning of its owner's upkeep, they remove a time counter. When the last is removed, they may play it without paying its mana cost. If it's a creature, it has haste.)

Patriar's Seal

{T}: Add one mana of any color.
{1}, {T}: Untap target legendary creature you control.

Urborg, Tomb of Yawgmoth

Each land is a Swamp in addition to its other land types.

Kaervek the Merciless

Whenever an opponent casts a spell, Kaervek deals damage equal to that spell's mana value to any target.

Worst Fears

You control target player during that player's next turn. Exile Worst Fears. (You see all cards that player could see and make all decisions for the player.)

Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Smoldering Marsh

({T}: Add {B} or {R}.)
This land enters tapped unless you control two or more basic lands.

Battlemage's Bracers

Equipped creature has haste.
Whenever an ability of equipped creature is activated, if it isn't a mana ability, you may pay {1}. If you do, copy that ability. You may choose new targets for the copy.
Equip {2}

Evolving Wilds

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

Retreat to Coralhelm

Landfall — Whenever a land you control enters, choose one —
• You may tap or untap target creature.
• Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Island

Exotic Orchard

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

Eyes of the Beholder

Target creature gets -11/-11 until end of turn.

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}

Mana Geyser

Add {R} for each tapped land your opponents control.

Shivan Reef

{T}: Add {C}.
{T}: Add {U} or {R}. This land deals 1 damage to you.

Archmage Emeritus

Magecraft — Whenever you cast or copy an instant or sorcery spell, draw a card.

Arcane Bombardment

Whenever you cast your first instant or sorcery spell each turn, exile an instant or sorcery card at random from your graveyard. Then copy each card exiled with this enchantment. You may cast any number of the copies without paying their mana costs.

Baleful Beholder

When this creature enters, choose one —
• Antimagic Cone — Each opponent sacrifices an enchantment of their choice.
• Fear Ray — Creatures you control gain menace until end of turn. (A creature with menace can't be blocked except by two or more creatures.)

Cabal Coffers

{2}, {T}: Add {B} for each Swamp you control.

Kess, Dissident Mage

Flying
Once during each of your turns, you may cast an instant or sorcery spell from your graveyard. If a spell cast this way would be put into your graveyard, exile it instead.

Swamp

Crosis's Charm

Choose one —
• Return target permanent to its owner's hand.
• Destroy target nonblack creature. It can't be regenerated.
• Destroy target artifact.

Terramorphic Expanse

Wand of Wonder

{4}, {T}: Roll a d20. Each opponent exiles cards from the top of their library until they exile an instant or sorcery card, then shuffles the rest into their library. You may cast up to X instant and/or sorcery spells from among cards exiled this way without paying their mana costs.
1—9 | X is one.
10—19 | X is two.
20 | X is three.

Drown in the Loch

Choose one —
• Counter target spell with mana value less than or equal to the number of cards in its controller's graveyard.
• Destroy target creature with mana value less than or equal to the number of cards in its controller's graveyard.

Solve the Equation

Search your library for an instant or sorcery card, reveal it, put it into your hand, then shuffle.

Threaten

Untap target creature and gain control of it until end of turn. That creature gains haste until end of turn. (It can attack and {T} this turn.)

Sanguine Morass

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

Bloodsoaked Insight

This spell costs {1} less to cast for each 1 life your opponents have lost this turn.
Target opponent exiles the top three cards of their library. Until the end of your next turn, you may play those cards. If you cast a spell this way, mana of any type can be spent to cast it.

Bloodsoaked Insight // Sanguine Morass

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.

Cormela, Glamour Thief

Haste
{1}, {T}: Add {U}{B}{R}. Spend this mana only to cast instant and/or sorcery spells.
When Cormela dies, return up to one target instant or sorcery card from your graveyard to your hand.

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.)

Illusionist's Bracers

Whenever an ability of equipped creature is activated, if it isn't a mana ability, copy that ability. You may choose new targets for the copy.
Equip {3}

Karazikar, the Eye Tyrant

Whenever you attack a player, tap target creature that player controls and goad it. (Until your next turn, that creature attacks each combat if able and attacks a player other than you if able.)
Whenever an opponent attacks another one of your opponents, you and the attacking player each draw a card and lose 1 life.

Crosis's Catacombs

When this land enters, sacrifice it unless you return a non-Lair land you control to its owner's hand.
{T}: Add {U}, {B}, or {R}.

Den of the Bugbear

If you control two or more other lands, this land enters tapped.
{T}: Add {R}.
{3}{R}: Until end of turn, this land becomes a 3/2 red Goblin creature with "Whenever this creature attacks, create a 1/1 red Goblin creature token that's tapped and attacking." It's still a land.

Fierce Guardianship

If you control a commander, you may cast this spell without paying its mana cost.
Counter target noncreature spell.

Bedevil

Destroy target artifact, creature, or planeswalker.

Sol Ring

Twinning Staff

If you would copy a spell one or more times, instead copy it that many times plus an additional time. You may choose new targets for the additional copy.
{7}, {T}: Copy target instant or sorcery spell you control. You may choose new targets for the copy.

Myriad Landscape

This land enters tapped.
{T}: Add {C}.
{2}, {T}, Sacrifice this land: Search your library for up to two basic land cards that share a land type, put them onto the battlefield tapped, then shuffle.

Oubliette

When this enchantment enters, target creature phases out until this enchantment leaves the battlefield. Tap that creature as it phases in this way. (Auras and Equipment phase out with it. While permanents are phased out, they're treated as though they don't exist.)

Leadership Vacuum

Target player returns each commander they control from the battlefield to the command zone.
Draw a card.

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.

Nightscape Familiar

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

Storm-Kiln Artist

This creature gets +1/+0 for each artifact you control.
Magecraft — Whenever you cast or copy an instant or sorcery spell, create a Treasure token.