Elf Warrior

Harmonize

Thornweald Archer

Reach (This creature can block creatures with flying.)
Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)

Dwynen's Elite

When this creature enters, if you control another Elf, create a 1/1 green Elf Warrior creature token.

Snakeskin Veil

Put a +1/+1 counter on target creature you control. It gains hexproof until end of turn. (It can't be the target of spells or abilities your opponents control.)

Priest of Titania

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

Forest

Giant Growth

Target creature gets +3/+3 until end of turn.

Llanowar Elves

Elvish Visionary

When Elvish Visionary enters, draw a card.

Tajuru Pathwarden

Vigilance (Attacking doesn't cause this creature to tap.)
Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)

Beast-Kin Ranger

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
Whenever another creature you control enters, this creature gets +1/+0 until end of turn.