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.

Patriar's Seal

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

Horizon Stone

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

Furnace of Rath

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

Bootleggers' Stash

Lands you control have "{T}: Create a Treasure token."

Victory Chimes

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

Dictate of Karametra

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

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.

Heartbeat of Spring

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

Llanowar Elves

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.

Raggadragga, Goreguts Boss

Each creature you control with a mana ability gets +2/+2.
Whenever a creature you control with a mana ability attacks, untap it.
Whenever you cast a spell, if at least seven mana was spent to cast it, untap target creature. It gets +7/+7 and gains trample until end of turn.

Dosan the Falling Leaf

Players can cast spells only during their own turns.

Harsh Mentor

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

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}.

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.

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.)

Torbran, Thane of Red Fell

If a red source you control would deal damage to an opponent or a permanent an opponent controls, it deals that much damage plus 2 instead.

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.

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.

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.

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.

Zhur-Taa Ancient

Magus of the Vineyard

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

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}.

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.