Zhur-Taa Ancient

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.

Eladamri's Vineyard

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

Spectral Searchlight

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

Tectonic Instability

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

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.

Mana Flare

Blinkmoth Urn

At the beginning of each player's first main phase, if Blinkmoth Urn is untapped, that player adds {C} for each artifact they control.

Tangleroot

Whenever a player casts a creature spell, that player adds {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}.

Shizuko, Caller of Autumn

At the beginning of each player's upkeep, that player adds {G}{G}{G}. Until end of turn, they don't lose this mana as steps and phases end.

Heartbeat of Spring

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.)

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.

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.

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.