Heartbeat of Spring

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

Nyxbloom Ancient

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

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

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

Vigilance
A player losing unspent mana causes that player to lose that much life.
{1}, {T}: Each player adds {B}{R}{G}.