Agatha of the Vile Cauldron

Activated abilities of creatures you control cost {X} less to activate, where X is Agatha of the Vile Cauldron's power. This effect can't reduce the mana in that cost to less than one mana.
{4}{R}{G}: Other creatures you control get +1/+1 and gain trample and haste until end of turn.

Tremble

Sting, the Glinting Dagger

Equipped creature gets +1/+1 and has haste.
At the beginning of each combat, untap equipped creature.
Equipped creature has first strike as long as it's blocking or blocked by a Goblin or Orc.
Equip {2}

Vexing Shusher

This spell can't be countered.
{R/G}: Target spell can't be countered.

Flowstone Flood

Buyback—Pay 3 life, Discard a card at random. (You may pay 3 life and discard a card at random in addition to any other costs as you cast this spell. If you do, put this card into your hand as it resolves.)
Destroy target land.

Stomping Ground

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

Blood Moon

Skyclave Relic

Kicker {3}
Indestructible
When Skyclave Relic enters, if it was kicked, create two tapped tokens that are copies of Skyclave Relic.
{T}: Add one mana of any color.

Ulamog, the Infinite Gyre

When you cast this spell, destroy target permanent.
Indestructible
Annihilator 4 (Whenever this creature attacks, defending player sacrifices four permanents.)
When Ulamog, the Infinite Gyre is put into a graveyard from anywhere, its owner shuffles their graveyard into their library.

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.

Smashing Success

Destroy target artifact or land. If an artifact is destroyed this way, create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Acidic Slime

Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)
When Acidic Slime enters, destroy target artifact, enchantment, or land.

Commune with Lava

Exile the top X cards of your library. Until the end of your next turn, you may play those cards.

Roxanne, Starfall Savant

Whenever Roxanne, Starfall Savant enters or attacks, create a tapped colorless artifact token named Meteorite with "When Meteorite enters, it deals 2 damage to any target" and "{T}: Add one mana of any color."
Whenever you tap an artifact token for mana, add one mana of any type that artifact token produced.

Legolas's Quick Reflexes

Split second (As long as this spell is on the stack, players can't cast spells or activate abilities that aren't mana abilities.)
Untap target creature. Until end of turn, it gains hexproof, reach, and "Whenever this creature becomes tapped, it deals damage equal to its power to up to one target creature."

Nyxbloom Ancient

Trample
If you tap a permanent for mana, it produces three times as much of that mana instead.

Dwarven Blastminer

{2}{R}, {T}: Destroy target nonbasic land.
Morph {R} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Devastation

Boseiju, Who Endures

{T}: Add {G}.
Channel — {1}{G}, Discard Boseiju, Who Endures: Destroy target artifact, enchantment, or nonbasic land an opponent controls. That player may search their library for a land card with a basic land type, put it onto the battlefield, then shuffle. This ability costs {1} less to activate for each legendary creature you control.

Fyndhorn Elves

Mind Stone

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

Creeping Mold

Destroy target artifact, enchantment, or land.

Wrenn and Six

+1: Return up to one target land card from your graveyard to your hand.
−1: Wrenn and Six deals 1 damage to any target.
−7: You get an emblem with "Instant and sorcery cards in your graveyard have retrace." (You may cast instant and sorcery cards from your graveyard by discarding a land card in addition to paying their other costs.)

Thrill of Possibility

As an additional cost to cast this spell, discard a card.
Draw two cards.

Goblin Anarchomancer

Each spell you cast that's red or green costs {1} less to cast.

The Mending of Dominaria

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I, II — Mill two cards, then you may return a creature card from your graveyard to your hand.
III — Return all land cards from your graveyard to the battlefield, then shuffle your graveyard into your library.

Undergrowth Recon

At the beginning of your upkeep, return target land card from your graveyard to the battlefield tapped.

Darksteel Citadel

Obliterate

This spell can't be countered.
Destroy all artifacts, creatures, and lands. They can't be regenerated.

Demand Answers

As an additional cost to cast this spell, sacrifice an artifact or discard a card.
Draw two cards.

Thresher Beast

Whenever Thresher Beast becomes blocked, defending player sacrifices a land.

Darksteel Forge

Artifacts you control have indestructible. (Effects that say "destroy" don't destroy them. Artifact creatures with indestructible can't be destroyed by damage.)

Galvanoth

At the beginning of your upkeep, you may look at the top card of your library. You may cast it without paying its mana cost if it's an instant or sorcery spell.

Moss Diamond

Moss Diamond enters tapped.
{T}: Add {G}.

Rain of Salt

Field of Ruin

{T}: Add {C}.
{2}, {T}, Sacrifice Field of Ruin: Destroy target nonbasic land an opponent controls. Each player searches their library for a basic land card, puts it onto the battlefield, then shuffles.

Akki Blizzard-Herder

When Akki Blizzard-Herder dies, each player sacrifices a land.

Tectonic Hellion

Haste
Whenever Tectonic Hellion attacks, each player who controls the most lands sacrifices two lands.

Epicenter

Target player sacrifices a land.
Threshold — Each player sacrifices all lands they control instead if seven or more cards are in your graveyard.

Big Score

As an additional cost to cast this spell, discard a card.
Draw two cards and create two Treasure tokens. (They're artifacts with "{T}, Sacrifice this artifact: Add one mana of any color.")

Klothys, God of Destiny

Indestructible
As long as your devotion to red and green is less than seven, Klothys isn't a creature.
At the beginning of your first main phase, exile target card from a graveyard. If it was a land card, add {R} or {G}. Otherwise, you gain 2 life and Klothys deals 2 damage to each opponent.

Rodeo Pyromancers

Whenever you cast your first spell each turn, add {R}{R}.

Waking the Trolls

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Destroy target land.
II — Put target land card from a graveyard onto the battlefield under your control.
III — Choose target opponent. If they control fewer lands than you, create a number of 4/4 green Troll Warrior creature tokens with trample equal to the difference.

Manabarbs

Whenever a player taps a land for mana, Manabarbs deals 1 damage to that player.

Terastodon

When Terastodon enters, you may destroy up to three target noncreature permanents. For each permanent put into a graveyard this way, its controller creates a 3/3 green Elephant creature token.

Bend or Break

Each player separates all nontoken lands they control into two piles. For each player, one of their piles is chosen by one of their opponents of their choice. Destroy all lands in the chosen piles. Tap all lands in the other piles.

Raze

As an additional cost to cast this spell, sacrifice a land.
Destroy target land.

Chimil, the Inner Sun

Spells you control can't be countered.
At the beginning of your end step, discover 5. (Exile cards from the top of your library until you exile a nonland card with mana value 5 or less. Cast it without paying its mana cost or put it into your hand. Put the rest on the bottom in a random order.)

Zo-Zu the Punisher

Whenever a land enters, Zo-Zu the Punisher deals 2 damage to that land's controller.

Demolish

Frenzied Tilling

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

Reclaiming Vines

Highland Forest

({T}: Add {R} or {G}.)
Highland Forest enters tapped.

Double Vision

Whenever you cast your first instant or sorcery spell each turn, copy that spell. You may choose new targets for the copy.

Sunder from Within

Regrowth

Return target card from your graveyard to your hand.

Worldsoul's Rage

Worldsoul's Rage deals X damage to any target. Put up to X land cards from your hand and/or graveyard onto the battlefield tapped.

Dryad's Revival

Return target card from your graveyard to your hand.
Flashback {4}{G} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

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 Arcane Bombardment. You may cast any number of the copies without paying their mana costs.

Fire Diamond

Fire Diamond enters tapped.
{T}: Add {R}.

Thoughts of Ruin

Each player sacrifices a land for each card in your hand.

Volatile Fault

{T}: Add {C}.
{1}, {T}, Sacrifice Volatile Fault: Destroy target nonbasic land an opponent controls. That player may search their library for a basic land card, put it onto the battlefield, then shuffle. You create a Treasure token.

Jokulhaups

Destroy all artifacts, creatures, and lands. They can't be regenerated.

Impending Disaster

At the beginning of your upkeep, if there are seven or more lands on the battlefield, sacrifice Impending Disaster and destroy all lands.

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.

Mwonvuli Acid-Moss

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

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.

Sandwurm Convergence

Creatures with flying can't attack you or planeswalkers you control.
At the beginning of your end step, create a 5/5 green Wurm creature token.

Aftershock

Destroy target artifact, creature, or land. Aftershock deals 3 damage to you.

Desecration Plague

Invader Parasite

Imprint — When Invader Parasite enters, exile target land.
Whenever a land an opponent controls with the same name as the exiled card enters, Invader Parasite deals 2 damage to that player.

Icefall

Destroy target artifact or land.
Recover {R}{R} (When a creature is put into your graveyard from the battlefield, you may pay {R}{R}. If you do, return this card from your graveyard to your hand. Otherwise, exile this card.)

The Millennium Calendar

Whenever you untap one or more permanents during your untap step, put that many time counters on The Millennium Calendar.
{2}, {T}: Double the number of time counters on The Millennium Calendar.
When there are 1,000 or more time counters on The Millennium Calendar, sacrifice it and each opponent loses 1,000 life.

Ulamog's Crusher

Annihilator 2 (Whenever this creature attacks, defending player sacrifices two permanents.)
Ulamog's Crusher attacks each combat if able.

Decimate

Destroy target artifact, target creature, target enchantment, and target land. (You can't cast this spell unless you have legal choices for all its targets.)

Patriar's Seal

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

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}

Terravore

Trample
Terravore's power and toughness are each equal to the number of land cards in all graveyards.

Darksteel Ingot

Indestructible (Effects that say "destroy" don't destroy this artifact.)
{T}: Add one mana of any color.

Llanowar Elves

Bust

Boom

Destroy target land you control and target land you don't control.

Boom // Bust

Lay Waste

Destroy target land.
Cycling {2} ({2}, Discard this card: Draw a card.)

Drownyard Temple

{T}: Add {C}.
{3}: Return Drownyard Temple from your graveyard to the battlefield tapped.

Decree of Annihilation

Exile all artifacts, creatures, and lands from the battlefield, all cards from all graveyards, and all cards from all hands.
Cycling {5}{R}{R} ({5}{R}{R}, Discard this card: Draw a card.)
When you cycle Decree of Annihilation, destroy all lands.

Rings of Brighthearth

Whenever you activate an ability, if it isn't a mana ability, you may pay {2}. If you do, copy that ability. You may choose new targets for the copy.

Deus of Calamity

Trample
Whenever Deus of Calamity deals 6 or more damage to an opponent, destroy target land that player controls.

Hedron Archive

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

Wreak Havoc

This spell can't be countered.
Destroy target artifact or land.

Artisan of Kozilek

When you cast this spell, you may return target creature card from your graveyard to the battlefield.
Annihilator 2 (Whenever this creature attacks, defending player sacrifices two permanents.)

Second Harvest

For each token you control, create a token that's a copy of that permanent.

Beast Within

Destroy target permanent. Its controller creates a 3/3 green Beast creature token.

Tamiyo's Safekeeping

Target permanent you control gains hexproof and indestructible until end of turn. You gain 2 life. (A permanent with hexproof and indestructible can't be the target of spells or abilities your opponents control. Damage and effects that say "destroy" don't destroy it.)

Abrade

Choose one —
• Abrade deals 3 damage to target creature.
• Destroy target artifact.

Orcish Settlers

{X}{X}{R}, {T}, Sacrifice Orcish Settlers: Destroy X target lands.

Detritivore

Detritivore's power and toughness are each equal to the number of nonbasic land cards in your opponents' graveyards.
Suspend X—{X}{3}{R}. X can't be 0. (Rather than cast this card from your hand, you may pay {X}{3}{R} and exile it with X time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost. It has haste.)
Whenever a time counter is removed from Detritivore while it's exiled, destroy target nonbasic land.

Ignite the Future

Exile the top three cards of your library. Until the end of your next turn, you may play those cards. If this spell was cast from a graveyard, you may play cards this way without paying their mana costs.
Flashback {7}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Elixir of Immortality

{2}, {T}: You gain 5 life. Shuffle Elixir of Immortality and your graveyard into their owner's library.

Cleansing Wildfire

Destroy target land. Its controller may search their library for a basic land card, put it onto the battlefield tapped, then shuffle.
Draw a card.

Annoyed Altisaur

Reach, trample
Cascade (When you cast this spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom in a random order.)

Demolition Field

{T}: Add {C}.
{2}, {T}, Sacrifice Demolition Field: Destroy target nonbasic land an opponent controls. That land's controller may search their library for a basic land card, put it onto the battlefield, then shuffle. You may search your library for a basic land card, put it onto the battlefield, then shuffle.

Thunderous Debut

Bargain (You may sacrifice an artifact, enchantment, or token as you cast this spell.)
Look at the top twenty cards of your library. You may reveal up to two creature cards from among them. If this spell was bargained, put the revealed cards onto the battlefield. Otherwise, put the revealed cards into your hand. Then shuffle.

Once and Future

Return target card from your graveyard to your hand. Put up to one other target card from your graveyard on top of your library. Exile Once and Future.
Adamant — If at least three green mana was spent to cast this spell, instead return those cards to your hand and exile Once and Future.

Keldon Firebombers

When Keldon Firebombers enters, each player sacrifices all lands they control except for three.

Unwinding Clock

Untap all artifacts you control during each other player's untap step.

The One Ring

Indestructible
When The One Ring enters, if you cast it, you gain protection from everything until your next turn.
At the beginning of your upkeep, you lose 1 life for each burden counter on The One Ring.
{T}: Put a burden counter on The One Ring, then draw a card for each burden counter on The One Ring.