Castle Garenbrig

Castle Garenbrig enters tapped unless you control a Forest.
{T}: Add {G}.
{2}{G}{G}, {T}: Add six {G}. Spend this mana only to cast creature spells or activate abilities of creatures.

Have

Collective Unconscious

Draw a card for each creature you control.

Llanowar Elves

Forest

Parallel Lives

If an effect would create one or more tokens under your control, it creates twice that many of those tokens instead.

Priest of Titania

{T}: Add {G} for each Elf on the battlefield.

Tendershoot Dryad

Ascend (If you control ten or more permanents, you get the city's blessing for the rest of the game.)
At the beginning of each upkeep, create a 1/1 green Saproling creature token.
Saprolings you control get +2/+2 as long as you have the city's blessing.

Nemata, Grove Guardian

{2}{G}: Create a 1/1 green Saproling creature token.
Sacrifice a Saproling: Saproling creatures get +1/+1 until end of turn.

Elvish Farmer

At the beginning of your upkeep, put a spore counter on Elvish Farmer.
Remove three spore counters from Elvish Farmer: Create a 1/1 green Saproling creature token.
Sacrifice a Saproling: You gain 2 life.

Fyndhorn Elves

Wirewood Lodge

{T}: Add {C}.
{G}, {T}: Untap target Elf.

Verdeloth the Ancient

Kicker {X} (You may pay an additional {X} as you cast this spell.)
Saproling creatures and other Treefolk creatures get +1/+1.
When Verdeloth the Ancient enters, if it was kicked, create X 1/1 green Saproling creature tokens.

Spontaneous Generation

Create a 1/1 green Saproling creature token for each card in your hand.

An-Havva Inn

You gain X plus 1 life, where X is the number of green creatures on the battlefield.

Gaea's Cradle

{T}: Add {G} for each creature you control.

Naturalize

Saproling Symbiosis

You may cast Saproling Symbiosis as though it had flash if you pay {2} more to cast it. (You may cast it any time you could cast an instant.)
Create a 1/1 green Saproling creature token for each creature you control.

Altar of Dementia

Sacrifice a creature: Target player mills cards equal to the sacrificed creature's power.