Sol Ring

Leyline of Abundance

If this card 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.

Horizon Stone

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

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.

Zhur-Taa Ancient

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

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.)

Rampant Growth

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

Manabarbs

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

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.

Seeker of Skybreak

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.

Dictate of Karametra

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

Dosan the Falling Leaf

Players can cast spells only during their own turns.

Llanowar Elves

Arcane Signet

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

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}.

Helix Pinnacle

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

Heartbeat of Spring

Stoneshaker Shaman

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

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.

Umbral Mantle

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