Horizon Stone

If you would lose unspent mana, that mana becomes colorless instead.

Magewright's Stone

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

Victory Chimes

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

Dictate of the Twin Gods

Flash
If a source would deal damage to a permanent or player, it deals double that damage to that permanent or player instead.

Exocrine

Ravenous (This creature enters with X +1/+1 counters on it. If X is 5 or more, draw a card when it enters.)
Bio-plasmic Barrage — When Exocrine enters, it deals X damage to each player and each other creature.

Rakdos Carnarium

Rakdos Carnarium enters tapped.
When Rakdos Carnarium enters, return a land you control to its owner's hand.
{T}: Add {B}{R}.

Mountain

Kaervek the Merciless

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

Forest

City on Fire

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
If a source you control would deal damage to a permanent or player, it deals triple that damage instead.

Electrodominance

Electrodominance deals X damage to any target. You may cast a spell with mana value X or less from your hand without paying its mana cost.

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.

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.)

Dictate of Karametra

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

Mana Web

Whenever a land an opponent controls is tapped for mana, tap all lands that player controls that could produce any type of mana that land could produce.

Leyline Tyrant

Flying
You don't lose unspent red mana as steps and phases end.
When Leyline Tyrant dies, you may pay any amount of {R}. When you do, it deals that much damage to any target.

Aberrant

Ravenous (This creature enters with X +1/+1 counters on it. If X is 5 or more, draw a card when it enters.)
Trample
Heavy Power Hammer — Whenever Aberrant deals combat damage to a player, destroy target artifact or enchantment that player controls.

Swamp

Genesis Hydra

When you cast this spell, reveal the top X cards of your library. You may put a nonland permanent card with mana value X or less from among them onto the battlefield. Then shuffle the rest into your library.
Genesis Hydra enters with X +1/+1 counters on it.

Cultivate

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.

Damnable Pact

Target player draws X cards and loses X life.

Tectonic Instability

Whenever a land enters, tap all lands its controller controls.

New Frontiers

Each player may search their library for up to X basic land cards and put them onto the battlefield tapped. Then each player who searched their library this way shuffles.

Sporocyst

Ravenous (This creature enters with X +1/+1 counters on it. If X is 5 or more, draw a card when it enters.)
Defender
Spore Chimney — When Sporocyst enters, search your library for up to X basic land cards, put them onto the battlefield tapped, then shuffle.

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}.

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.

Klauth's Will

Choose one. If you control a commander as you cast this spell, you may choose both instead.
• Breathe Flame — Klauth's Will deals X damage to each creature without flying.
• Smash Relics — Destroy up to X target artifacts and/or enchantments.

Read the Bones

Scry 2, then draw two cards. You lose 2 life. (To scry 2, look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Ziatora's Proving Ground

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

Fiery Emancipation

If a source you control would deal damage to a permanent or player, it deals triple that damage to that permanent or player instead.

Umbral Mantle

Equipped creature has "{3}, {Q}: This creature gets +2/+2 until end of turn." ({Q} is the untap symbol.)
Equip {0}

War's Toll

Whenever an opponent taps a land for mana, tap all lands that player controls.
If a creature an opponent controls attacks, all creatures that opponent controls attack if able.

Erebos's Intervention

Choose one —
• Target creature gets -X/-X until end of turn. You gain X life.
• Exile up to twice X target cards from graveyards.

Torment of Hailfire

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

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.

Tyvar's Stand

Target creature you control gets +X/+X and gains hexproof and indestructible until end of turn. (A creature 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.)

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.

Vexing Shusher

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

Painful Quandary

Whenever an opponent casts a spell, that player loses 5 life unless they discard a card.

Havoc Festival

Players can't gain life.
At the beginning of each player's upkeep, that player loses half their life, rounded up.

Xantcha, Sleeper Agent

Xantcha, Sleeper Agent enters 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.

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.

Lavalanche

Lavalanche deals X damage to target player or planeswalker and each creature that player or that planeswalker's controller controls.

Crackle with Power

Crackle with Power deals five times X damage to each of up to X targets.

Savage Lands

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

Shivan Devastator

Flying, haste
Shivan Devastator enters with X +1/+1 counters on it.

Jaya's Immolating Inferno

(You may cast a legendary sorcery only if you control a legendary creature or planeswalker.)
Jaya's Immolating Inferno deals X damage to each of up to three targets.

Spectral Searchlight

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

Mana Flare

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

Heartbeat of Spring

Rosheen Meanderer

{T}: Add {C}{C}{C}{C}. Spend this mana only on costs that contain {X}.

Wound Reflection

At the beginning of each end step, each opponent loses life equal to the life they lost this turn. (Damage causes loss of life.)

Exsanguinate

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

Sol Ring

Golgari Rot Farm

Golgari Rot Farm enters tapped.
When Golgari Rot Farm enters, return a land you control to its owner's hand.
{T}: Add {B}{G}.

Arcane Signet

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

Nyxbloom Ancient

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

Gruul Turf

Gruul Turf enters tapped.
When Gruul Turf enters, return a land you control to its owner's hand.
{T}: Add {R}{G}.

Animist's Awakening

Reveal the top X cards of your library. Put all land cards from among them onto the battlefield tapped and the rest on the bottom of your library in a random order.
Spell mastery — If there are two or more instant and/or sorcery cards in your graveyard, untap those lands.

Mana Reflection

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

Zhur-Taa Ancient

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.

Harmonize

Apocalypse Hydra

Apocalypse Hydra enters with X +1/+1 counters on it. If X is 5 or more, it enters with an additional X +1/+1 counters on it.
{1}{R}, Remove a +1/+1 counter from Apocalypse Hydra: It deals 1 damage to any target.

Hungering Hydra

Hungering Hydra enters with X +1/+1 counters on it.
Hungering Hydra can't be blocked by more than one creature.
Whenever Hungering Hydra is dealt damage, put that many +1/+1 counters on it. (It must survive the damage to get the counters.)

Seeker of Skybreak

Ignoble Hierarch

Exalted (Whenever a creature you control attacks alone, that creature gets +1/+1 until end of turn.)
{T}: Add {B}, {R}, or {G}.

Magus of the Vineyard

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

Magus of the Candelabra

Diabolic Tutor

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

Clan Defiance

Choose one or more —
• Clan Defiance deals X damage to target creature with flying.
• Clan Defiance deals X damage to target creature without flying.
• Clan Defiance deals X damage to target player or planeswalker.

Vampiric Tutor

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

Sword of the Paruns

As long as equipped creature is tapped, tapped creatures you control get +2/+0.
As long as equipped creature is untapped, untapped creatures you control get +0/+2.
{3}: You may tap or untap equipped creature.
Equip {3}

Killing Wave

For each creature, its controller sacrifices it unless they pay X life.

Stonecoil Serpent

Reach, trample, protection from multicolored
Stonecoil Serpent enters with X +1/+1 counters on it.

Command Tower

Banefire

Banefire deals X damage to any target.
If X is 5 or more, this spell can't be countered and the damage can't be prevented.

Zhur-Taa Druid

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

Leyline of Abundance

If Leyline of Abundance is in your opening hand, you may begin the game with it on the battlefield.
Whenever you tap a creature for mana, add an additional {G}.
{6}{G}{G}: Put a +1/+1 counter on each creature you control.

Belbe, Corrupted Observer

At the beginning of each postcombat main phase, the active player adds {C}{C} for each of your opponents who lost life this turn. (Damage causes loss of life.)