Vine Trellis

Defender (This creature can't attack.)
{T}: Add {G}.

Devoted Druid

{T}: Add {G}.
Put a -1/-1 counter on this creature: Untap this creature.

Elvish Mystic

Sanctum Weaver

{T}: Add X mana of any one color, where X is the number of enchantments you control.

Fyndhorn Elves

Karametra, God of Harvests

Indestructible
As long as your devotion to green and white is less than seven, Karametra isn't a creature.
Whenever you cast a creature spell, you may search your library for a Forest or Plains card, put it onto the battlefield tapped, then shuffle.

Manakin

Ilysian Caryatid

{T}: Add one mana of any color. If you control a creature with power 4 or greater, add two mana of any one color instead.

Joraga Treespeaker

Level up {1}{G} ({1}{G}: Put a level counter on this. Level up only as a sorcery.)
LEVEL 1-4
1/2
{T}: Add {G}{G}.
LEVEL 5+
1/4
Elves you control have "{T}: Add {G}{G}."

Katilda, Dawnhart Prime

Protection from Werewolves
Human creatures you control have "{T}: Add one mana of any of this creature's colors."
{4}{G}{W}, {T}: Put a +1/+1 counter on each creature you control.

Lotus Cobra

Landfall — Whenever a land you control enters, add one mana of any color.

Magus of the Vineyard

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

Llanowar Elves

Paradise Druid

This creature has hexproof as long as it's untapped. (It can't be the target of spells or abilities your opponents control.)
{T}: Add one mana of any color.

Poison Dart Frog

Reach
{T}: Add one mana of any color.
{2}: This creature gains deathtouch until end of turn.

Ornithopter of Paradise

Tangled Vale

Tangled Florahedron

Tangled Florahedron // Tangled Vale

Copper Myr

Hedron Crawler

{T}: Add {C}. ({C} represents colorless mana.)

Leafkin Druid

{T}: Add {G}. If you control four or more creatures, add {G}{G} instead.