Green Sun's Twilight

Reveal the top X plus one cards of your library. Choose a creature card and/or a land card from among them. Put those cards into your hand and the rest on the bottom of your library in a random order. If X is 5 or more, instead put the chosen cards onto the battlefield or into your hand and the rest on the bottom of your library in a random order.

Smoldering Marsh

({T}: Add {B} or {R}.)
Smoldering Marsh enters the battlefield tapped unless you control two or more basic lands.

Mana-Charged Dragon

Flying, trample
Join forces — Whenever Mana-Charged Dragon attacks or blocks, each player starting with you may pay any amount of mana. Mana-Charged Dragon gets +X/+0 until end of turn, where X is the total amount of mana paid this way.

Lava-Field Overlord

Assist (Another player can pay up to {7} of this spell's cost.)
Flying
When Lava-Field Overlord enters the battlefield, it deals 4 damage to target creature an opponent controls.

Undergrowth Stadium

Undergrowth Stadium enters the battlefield tapped unless you have two or more opponents.
{T}: Add {B} or {G}.

Keeper of Progenitus

Whenever a player taps a Mountain, Forest, or Plains for mana, that player adds one mana of any type that land produced.

Manabarbs

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

Gift of Growth

Kicker {2} (You may pay an additional {2} as you cast this spell.)
Untap target creature. It gets +2/+2 until end of turn. If this spell was kicked, that creature gets +4/+4 until end of turn instead.

Savage Lands

Savage Lands enters the battlefield tapped.
{T}: Add {B}, {R}, or {G}.

Evolving Wilds

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

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."

Spire Garden

Spire Garden enters the battlefield tapped unless you have two or more opponents.
{T}: Add {R} or {G}.

Dragonskull Summit

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

Putrefy

Destroy target artifact or creature. It can't be regenerated.

Overgrown Tomb

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

Assassin's Trophy

Destroy target permanent an opponent controls. Its controller may search their library for a basic land card, put it onto the battlefield, then shuffle.

Puppet Strings

{2}, {T}: You may tap or untap target creature.

Mana Reflection

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

Seedborn Muse

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

Mountain

Exsanguinate

Each opponent loses X life. You gain life equal to the life lost this way.

Eladamri's Vineyard

At the beginning of each player's precombat main phase, that player adds {G}{G}.

Deathcap Glade

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

Rug of Smothering

Flying
Whenever a player casts a spell, they lose 1 life for each spell they've cast this turn.

Feral Hydra

Feral Hydra enters the battlefield with X +1/+1 counters on it.
{3}: Put a +1/+1 counter on Feral Hydra. Any player may activate this ability.

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control.)
Equip {1}

Rockfall Vale

Rockfall Vale enters the battlefield tapped unless you control two or more other lands.
{T}: Add {R} or {G}.

Gruul Signet

Woodland Cemetery

Woodland Cemetery enters the battlefield tapped unless you control a Swamp or a Forest.
{T}: Add {B} or {G}.

Magewright's Stone

{1}, {T}: Untap target creature that has an activated ability with {T} in its cost.

Xantcha, Sleeper Agent

Xantcha, Sleeper Agent enters the battlefield under the control of an opponent of your choice.
Xantcha attacks each combat if able and can't attack its owner or planeswalkers its owner controls.
{3}: Xantcha's controller loses 2 life and you draw a card. Any player may activate this ability.

Command Tower

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

Kodama's Reach

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.

Power Surge

At the beginning of each player's upkeep, Power Surge deals X damage to that player, where X is the number of untapped lands they controlled at the beginning of this turn.

Staff of Domination

{1}: Untap Staff of Domination.
{2}, {T}: You gain 1 life.
{3}, {T}: Untap target creature.
{4}, {T}: Tap target creature.
{5}, {T}: Draw a card.

Yurlok of Scorch Thrash

Vigilance
A player losing unspent mana causes that player to lose that much life.
{1}, {T}: Each player adds {B}{R}{G}.

Bojuka Bog

Bojuka Bog enters the battlefield tapped.
When Bojuka Bog enters the battlefield, exile target player's graveyard.
{T}: Add {B}.

Arcane Signet

Heroic Intervention

Permanents you control gain hexproof and indestructible until end of turn.

Ornamental Courage

Untap target creature. It gets +1/+3 until end of turn.

Comet Storm

Multikicker {1} (You may pay an additional {1} any number of times as you cast this spell.)
Choose any target, then choose another target for each time this spell was kicked. Comet Storm deals X damage to each of them.

Helix Pinnacle

Shroud (This enchantment can't be the target of spells or abilities.)
{X}: Put X tower counters on Helix Pinnacle.
At the beginning of your upkeep, if there are 100 or more tower counters on Helix Pinnacle, you win the game.

Cultivate

Gang Up

Assist (Another player can pay up to {X} of this spell's cost. You choose the value of X.)
Destroy target creature with power X or less.

Deadly Designs

{2}: Put a plot counter on Deadly Designs. Any player may activate this ability.
When there are five or more plot counters on Deadly Designs, sacrifice it. If you do, destroy up to two target creatures.

Capricopian

Capricopian enters the battlefield with X +1/+1 counters on it.
{2}: Put a +1/+1 counter on Capricopian, then you may reselect which player Capricopian is attacking. Only the player Capricopian is attacking may activate this ability and only during the declare attackers step. (It can't attack its controller.)

Fan Favorite

Assist (Another player can pay up to {3} of this spell's cost.)
{2}: Fan Favorite gets +1/+1 until end of turn. Any player may activate this ability.

Sol Ring

Bear Umbra

Enchant creature
Enchanted creature gets +2/+2 and has "Whenever this creature attacks, untap all lands you control."
Totem armor (If enchanted creature would be destroyed, instead remove all damage from it and destroy this Aura.)

Magus of the Vineyard

Beast Within

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

Collective Voyage

Join forces — Starting with you, each player may pay any amount of mana. Each player searches their library for up to X basic land cards, where X is the total amount of mana paid this way, puts them onto the battlefield tapped, then shuffles.

Thousand-Year Elixir

You may activate abilities of creatures you control as though those creatures had haste.
{1}, {T}: Untap target creature.

Scytheclaw Raptor

Whenever a player casts a spell, if it's not their turn, Scytheclaw Raptor deals 4 damage to them.

Nyxbloom Ancient

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

Stoneshaker Shaman

At the beginning of each player's end step, that player sacrifices an untapped land.

Yavimaya, Cradle of Growth

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

Eternal Witness

When Eternal Witness enters the battlefield, you may return target card from your graveyard to your hand.

Stomping Ground

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

Dictate of Karametra

Flash
Whenever a player taps a land for mana, that player adds one mana of any type that land produced.

Forest

Terminate

Destroy target creature. It can't be regenerated.

Citadel of Pain

At the beginning of each player's end step, Citadel of Pain deals X damage to that player, where X is the number of untapped lands they control.

Bigger on the Inside

Enchant artifact or land
Enchanted permanent has "{T}: Target player adds two mana of any one color. The next spell they cast this turn has cascade." (When they cast their next spell, they exile cards from the top of their library until they exile a nonland card that costs less. They may cast it without paying its mana cost. They put the exiled cards on the bottom in a random order.)

Overabundance

Whenever a player taps a land for mana, that player adds one mana of any type that land produced, and Overabundance deals 1 damage to the player.

Mana Flare

Whenever a player taps a land for mana, that player adds one mana of any type that land produced.

Heartbeat of Spring

Tyvar, Jubilant Brawler

You may activate abilities of creatures you control as though those creatures had haste.
+1: Untap up to one target creature.
−2: Mill three cards, then you may return a creature card with mana value 2 or less from your graveyard to the battlefield.

Rootbound Crag

Rootbound Crag enters the battlefield tapped unless you control a Mountain or a Forest.
{T}: Add {R} or {G}.

Luxury Suite

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

Patriar's Seal

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

Xira Arien

Flying
{B}{R}{G}, {T}: Target player draws a card.

Victory Chimes

Untap Victory Chimes during each other player's untap step.
{T}: A player of your choice adds {C}.

Ziatora's Proving Ground

({T}: Add {B}, {R}, or {G}.)
Ziatora's Proving Ground enters the battlefield tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)

Kaervek the Merciless

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

Blood Crypt

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

Swamp

Zhur-Taa Ancient

Zhur-Taa Druid

{T}: Add {G}.
Whenever you tap Zhur-Taa Druid for mana, it deals 1 damage to each opponent.

Seeker of Skybreak

Omnath, Locus of Mana

You don't lose unspent green mana as steps and phases end.
Omnath, Locus of Mana gets +1/+1 for each unspent green mana you have.

Aim High

Untap target creature. It gets +2/+2 and gains reach until end of turn. (It can block creatures with flying.)

Bloodborn Scoundrels

Assist (Another player can pay up to {5} of this spell's cost.)
When Bloodborn Scoundrels enters the battlefield, target opponent loses 2 life and you gain 2 life.

Heartwood Storyteller

Whenever a player casts a noncreature spell, each of that player's opponents may draw a card.

Spectral Searchlight

{T}: Choose a player. That player adds one mana of any color they choose.

Terramorphic Expanse

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