Koma, Cosmos Serpent

This spell can't be countered.
At the beginning of each upkeep, create a 3/3 blue Serpent creature token named Koma's Coil.
Sacrifice another Serpent: Choose one —
• Tap target permanent. Its activated abilities can't be activated this turn.
• Koma gains indestructible until end of turn.

Overgrown Tomb

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

Three Visits

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

Hallowed Fountain

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

Maelstrom Nexus

The first spell you cast each turn has cascade. (When you cast your first 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.)

Yavimaya Hollow

{T}: Add {C}.
{G}, {T}: Regenerate target creature.

Ulamog, the Ceaseless Hunger

When you cast this spell, exile two target permanents.
Indestructible
Whenever Ulamog attacks, defending player exiles the top twenty cards of their library.

Spara's Headquarters

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

Surrak Dragonclaw

Flash
This spell can't be countered.
Creature spells you control can't be countered.
Other creatures you control have trample.

Kellan, the Kid

Flying, lifelink
Whenever you cast a spell from anywhere other than your hand, you may cast a permanent spell with equal or lesser mana value from your hand without paying its mana cost. If you don't, you may put a land card from your hand onto the battlefield.

Disallow

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

Bloodstained Mire

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

Muddle the Mixture

Counter target instant or sorcery spell.
Transmute {1}{U}{U} ({1}{U}{U}, Discard this card: Search your library for a card with the same mana value as this card, reveal it, put it into your hand, then shuffle. Transmute only as a sorcery.)

Verdant Catacombs

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

Command Tower

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

Atraxa, Grand Unifier

Flying, vigilance, deathtouch, lifelink
When Atraxa enters, reveal the top ten cards of your library. For each card type, you may put a card of that type from among the revealed cards into your hand. Put the rest on the bottom of your library in a random order. (Artifact, battle, creature, enchantment, instant, land, planeswalker, and sorcery are card types.)

Primevals' Glorious Rebirth

(You may cast a legendary sorcery only if you control a legendary creature or planeswalker.)
Return all legendary permanent cards from your graveyard to the battlefield.

Sacred Foundry

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

Kozilek, Butcher of Truth

When you cast this spell, draw four cards.
Annihilator 4 (Whenever this creature attacks, defending player sacrifices four permanents of their choice.)
When Kozilek is put into a graveyard from anywhere, its owner shuffles their graveyard into their library.

Marsh Flats

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

Raffine's Tower

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

Zagoth Triome

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

Teferi's Protection

Until your next turn, your life total can't change and you gain protection from everything. All permanents you control phase out. (While they're phased out, they're treated as though they don't exist. They phase in before you untap during your untap step.)
Exile Teferi's Protection.

Godless Shrine

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

Pact of Negation

Counter target spell.
At the beginning of your next upkeep, pay {3}{U}{U}. If you don't, you lose the game.

Shanid, Sleepers' Scourge

Menace
Other legendary creatures you control have menace.
Whenever you play a legendary land or cast a legendary spell, you draw a card and you lose 1 life.

Ruinous Ultimatum

Destroy all nonland permanents your opponents control.

Blightsteel Colossus

Trample, infect, indestructible
If Blightsteel Colossus would be put into a graveyard from anywhere, reveal Blightsteel Colossus and shuffle it into its owner's library instead.

Defense of the Heart

At the beginning of your upkeep, if an opponent controls three or more creatures, sacrifice this enchantment, search your library for up to two creature cards, put those cards onto the battlefield, then shuffle.

Vampiric Tutor

Search your library for a card, then shuffle and put that card on top. You lose 2 life.

Rhystic Study

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

Flooded Strand

{T}, Pay 1 life, Sacrifice this land: Search your library for a Plains or Island card, put it onto the battlefield, then shuffle.

Savai Triome

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

City of Brass

Whenever this land becomes tapped, it deals 1 damage to you.
{T}: Add one mana of any color.

Jegantha, the Wellspring

Companion — No card in your starting deck has more than one of the same mana symbol in its mana cost. (If this card is your chosen companion, you may put it into your hand from outside the game for {3} as a sorcery.)
{T}: Add {W}{U}{B}{R}{G}. This mana can't be spent to pay generic mana costs.

Volrath's Stronghold

{T}: Add {C}.
{1}{B}, {T}: Put target creature card from your graveyard on top of your library.

Dovin's Veto

This spell can't be countered.
Counter target noncreature spell.

Avacyn, Angel of Hope

Flying, vigilance, indestructible
Other permanents you control have indestructible.

Ulamog, the Defiler

When you cast this spell, target opponent exiles the top half of their library, rounded up.
Ward—Sacrifice two permanents.
Ulamog enters with a number of +1/+1 counters on it equal to the greatest mana value among cards in exile.
Ulamog has annihilator X, where X is the number of +1/+1 counters on it.

Force of Will

You may pay 1 life and exile a blue card from your hand rather than pay this spell's mana cost.
Counter target spell.

The Great Henge

This spell costs {X} less to cast, where X is the greatest power among creatures you control.
{T}: Add {G}{G}. You gain 2 life.
Whenever a nontoken creature you control enters, put a +1/+1 counter on it and draw a card.

Kethis, the Hidden Hand

Legendary spells you cast cost {1} less to cast.
Exile two legendary cards from your graveyard: Until end of turn, each legendary card in your graveyard gains "You may play this card from your graveyard."

Arcane Signet

Skyshroud Claim

Search your library for up to two Forest cards, put them onto the battlefield, then shuffle.

Watery Grave

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

Wasteland

{T}: Add {C}.
{T}, Sacrifice this land: Destroy target nonbasic land.

Polluted Delta

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

Vraska Joins Up

When Vraska Joins Up enters, put a deathtouch counter on each creature you control.
Whenever a legendary creature you control deals combat damage to a player, draw a card.

Faeburrow Elder

Vigilance
This creature gets +1/+1 for each color among permanents you control.
{T}: For each color among permanents you control, add one mana of that color.

Iroas, God of Victory

Indestructible
As long as your devotion to red and white is less than seven, Iroas isn't a creature.
Creatures you control have menace.
Prevent all damage that would be dealt to attacking creatures you control.

Kenrith, the Returned King

{R}: All creatures gain trample and haste until end of turn.
{1}{G}: Put a +1/+1 counter on target creature.
{2}{W}: Target player gains 5 life.
{3}{U}: Target player draws a card.
{4}{B}: Put target creature card from a graveyard onto the battlefield under its owner's control.

Smothering Tithe

Whenever an opponent draws a card, that player may pay {2}. If the player doesn't, you create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Steam Vents

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

Survival of the Fittest

{G}, Discard a creature card: Search your library for a creature card, reveal that card, put it into your hand, then shuffle.

Indatha Triome

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

Reki, the History of Kamigawa

Whenever you cast a legendary spell, draw a card.

Raugrin Triome

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

Xander's Lounge

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

Consecrated Sphinx

Flying
Whenever an opponent draws a card, you may draw two cards.

Misty Rainforest

{T}, Pay 1 life, Sacrifice this land: Search your library for a Forest or Island card, put it onto the battlefield, then shuffle.

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.")

Birds of Paradise

Scalding Tarn

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

Jetmir's Garden

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

Fierce Guardianship

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

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.)

Demonic Tutor

Search your library for a card, put that card into your hand, then shuffle.

Jodah, Archmage Eternal

Flying
You may pay {W}{U}{B}{R}{G} rather than pay the mana cost for spells you cast.

Mana Drain

Counter target spell. At the beginning of your next main phase, add an amount of {C} equal to that spell's mana value.

Windswept Heath

{T}, Pay 1 life, Sacrifice this land: Search your library for a Forest or Plains card, put it onto the battlefield, then shuffle.

Farseek

Search your library for a Plains, Island, Swamp, or Mountain card, put it onto the battlefield tapped, then shuffle.

Arid Mesa

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

It That Betrays

Annihilator 2 (Whenever this creature attacks, defending player sacrifices two permanents of their choice.)
Whenever an opponent sacrifices a nontoken permanent, put that card onto the battlefield under your control.

Jhoira, Weatherlight Captain

Whenever you cast a historic spell, draw a card. (Artifacts, legendaries, and Sagas are historic.)

Ulamog, the Infinite Gyre

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

Jodah, the Unifier

Legendary creatures you control get +X/+X, where X is the number of legendary creatures you control.
Whenever you cast a legendary spell from your hand, exile cards from the top of your library until you exile a legendary nonland card with lesser mana value. You may cast that card without paying its mana cost. Put the rest on the bottom of your library in a random order.

Guardian Project

Whenever a nontoken creature you control enters, if it doesn't have the same name as another creature you control or a creature card in your graveyard, draw a card.

Sigarda, Font of Blessings

Flying
Other permanents you control have hexproof.
You may look at the top card of your library any time.
You may cast Angel spells and Human spells from the top of your library.

Emrakul, the Promised End

This spell costs {1} less to cast for each card type among cards in your graveyard.
When you cast this spell, you gain control of target opponent during that player's next turn. After that turn, that player takes an extra turn.
Flying, trample, protection from instants

Force of Negation

If it's not your turn, you may exile a blue card from your hand rather than pay this spell's mana cost.
Counter target noncreature spell. If that spell is countered this way, exile it instead of putting it into its owner's graveyard.

Bloom Tender

{T}: For each color among permanents you control, add one mana of that color.

Koma, World-Eater

This spell can't be countered.
Trample, ward {4}
Whenever Koma deals combat damage to a player, create four 3/3 blue Serpent creature tokens named Koma's Coil.

Eerie Ultimatum

Return any number of permanent cards with different names from your graveyard to the battlefield.

Ketria Triome

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

Stomping Ground

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

Ziatora's Proving Ground

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

Mana Confluence

{T}, Pay 1 life: Add one mana of any color.

Sol Ring

Nature's Lore

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

Breeding Pool

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

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.

Ragavan, Nimble Pilferer

Whenever Ragavan deals combat damage to a player, create a Treasure token and exile the top card of that player's library. Until end of turn, you may cast that card.
Dash {1}{R} (You may cast this spell for its dash cost. If you do, it gains haste, and it's returned from the battlefield to its owner's hand at the beginning of the next end step.)

Akroma's Memorial

Creatures you control have flying, first strike, vigilance, trample, haste, and protection from black and from red.

Blood Crypt

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

Last March of the Ents

This spell can't be countered.
Draw cards equal to the greatest toughness among creatures you control, then put any number of creature cards from your hand onto the battlefield.

Wooded Foothills

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

Temple Garden

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

Flare of Denial

You may sacrifice a nontoken blue creature rather than pay this spell's mana cost.
Counter target spell.

Swan Song

Counter target enchantment, instant, or sorcery spell. Its controller creates a 2/2 blue Bird creature token with flying.

Vega, the Watcher

Flying
Whenever you cast a spell from anywhere other than your hand, draw a card.