Canopy Tactician

Other Elves you control get +1/+1.
{T}: Add {G}{G}{G}.

Elvish Archdruid

Other Elf creatures you control get +1/+1.
{T}: Add {G} for each Elf you control.

Yavimaya, Cradle of Growth

Each land is a Forest in addition to its other land types.

Beast Whisperer

Whenever you cast a creature spell, draw a card.

Forest

Realmwalker

Changeling (This card is every creature type.)
As Realmwalker enters, choose a creature type.
You may look at the top card of your library any time.
You may cast creature spells of the chosen type from the top of your library.

Oracle of Mul Daya

You may play an additional land on each of your turns.
Play with the top card of your library revealed.
You may play lands from the top of your library.

Elvish Champion

Other Elf creatures get +1/+1 and have forestwalk. (They can't be blocked as long as defending player controls a Forest.)

Priest of Titania

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

Heedless One

Trample
Heedless One's power and toughness are each equal to the number of Elves on the battlefield.

Lys Alana Huntmaster

Whenever you cast an Elf spell, you may create a 1/1 green Elf Warrior creature token.

Elvish Promenade

Create a 1/1 green Elf Warrior creature token for each Elf you control.

Llanowar Elves

Elvish Warmaster

Whenever one or more other Elves you control enter, create a 1/1 green Elf Warrior creature token. This ability triggers only once each turn.
{5}{G}{G}: Elves you control get +2/+2 and gain deathtouch until end of turn.