Elvish Champion

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

Elvish Mystic

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.

Fyndhorn Elves

Timberwatch Elf

{T}: Target creature gets +X/+X until end of turn, where X is the number of Elves on the battlefield.

Beast Whisperer

Whenever you cast a creature spell, draw a card.

Wirewood Channeler

{T}: Add X mana of any one color, where X is the number of Elves on the battlefield.

Reclamation Sage

When Reclamation Sage enters, you may destroy target artifact or enchantment.

Priest of Titania

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

Llanowar Elves

Freyalise, Llanowar's Fury

+2: Create a 1/1 green Elf Druid creature token with "{T}: Add {G}."
−2: Destroy target artifact or enchantment.
−6: Draw a card for each green creature you control.
Freyalise, Llanowar's Fury can be your commander.