Omnath, Locus of Mana

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

Rampant Growth

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

Heroic Intervention

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

Citadel of Pain

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

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.

Swamp

Heartbeat of Spring

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

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.)

Farseek

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

Grip of Desolation

Devoid (This card has no color.)
Exile target creature and target land.

Managorger Hydra

Trample
Whenever a player casts a spell, put a +1/+1 counter on this creature.

Victory Chimes

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

Kaervek the Merciless

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

Burning Earth

Whenever a player taps a nonbasic land for mana, this enchantment deals 1 damage to that player.

Magewright's Stone

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

Seedborn Muse

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

Sol Ring

Polluted Bonds

Whenever a land an opponent controls enters, that player loses 2 life and you gain 2 life.

Magus of the Candelabra

Lightning Greaves

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.)
Equip {0}

Vexing Shusher

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

Exquisite Blood

Whenever an opponent loses life, you gain that much life.

Thousand-Year Elixir

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

Merciless Resolve

As an additional cost to cast this spell, sacrifice a creature or land.
Draw two cards.

Krosan Grip

Split second (As long as this spell is on the stack, players can't cast spells or activate abilities that aren't mana abilities.)
Destroy target artifact or enchantment.

Desolation

At the beginning of each end step, each player who tapped a land for mana this turn sacrifices a land of their choice. This enchantment deals 2 damage to each player who sacrificed a Plains this way.

Zhur-Taa Ancient

Nyxbloom Ancient

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

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.

Arcane Signet

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

Power Surge

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

Mountain

Mana Geyser

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

Blood Moon

Exotic Orchard

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

Tempt with Discovery

Tempting offer — Search your library for a land card and put it onto the battlefield. Each opponent may search their library for a land card and put it onto the battlefield. For each opponent who searches a library this way, search your library for a land card and put it onto the battlefield. Then each player who searched a library this way shuffles.

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}.

Avatar of the Resolute

Reach, trample
This creature enters with a +1/+1 counter on it for each other creature you control with a +1/+1 counter on it.

Crackle with Power

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

Overabundance

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

Birds of Paradise

Reliquary Tower

You have no maximum hand size.
{T}: Add {C}.

Price of Glory

Whenever a player taps a land for mana, if it's not that player's turn, destroy that land.

Lavalanche

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

Zhur-Taa Druid

{T}: Add {G}.
Whenever you tap this creature for mana, it deals 1 damage to each opponent.

Giant Solifuge

({R/G} can be paid with either {R} or {G}.)
Trample; haste; shroud (This creature can't be the target of spells or abilities.)

Cultivate

Immolation Shaman

Whenever an opponent activates an ability of an artifact, creature, or land that isn't a mana ability, this creature deals 1 damage to that player.
{3}{R}{R}: This creature gets +3/+3 and gains menace until end of turn.

Desolation Twin

When you cast this spell, create a 10/10 colorless Eldrazi creature token.

Blasphemous Act

This spell costs {1} less to cast for each creature on the battlefield.
Blasphemous Act deals 13 damage to each creature.

Mana Flare

Veteran Explorer

When this creature dies, each player may search their library for up to two basic land cards, put them onto the battlefield, then shuffle.

Forest

Nature's Lore

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

Xantcha, Sleeper Agent

Xantcha 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.

Horizon Stone

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

Urborg, Tomb of Yawgmoth

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

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}.

Staff of Domination

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

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.

Mana Cache

At the beginning of each player's end step, put a charge counter on this enchantment for each untapped land that player controls.
Remove a charge counter from this enchantment: Add {C}. Any player may activate this ability but only during their turn before the end step.

Three Visits

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

Yavimaya, Cradle of Growth

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

Leyline Tyrant

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

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.

Harsh Mentor

Whenever an opponent activates an ability of an artifact, creature, or land on the battlefield, if it isn't a mana ability, this creature deals 2 damage to that player.

Dictate of Karametra

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