Priest of Titania

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

Circle of Dreams Druid

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

Forest

Llanowar Elves

Elvish Mystic

Elvish Archdruid

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

Boreal Druid

Regal Force

When Regal Force enters, draw a card for each green creature you control.

Fyndhorn Elves

Mountain

Raggadragga, Goreguts Boss

Each creature you control with a mana ability gets +2/+2.
Whenever a creature you control with a mana ability attacks, untap it.
Whenever you cast a spell, if at least seven mana was spent to cast it, untap target creature. It gets +7/+7 and gains trample until end of turn.