Elvish Vanguard

Whenever another Elf enters, put a +1/+1 counter on Elvish Vanguard.

Forest

Quirion Ranger

Return a Forest you control to its owner's hand: Untap target creature. Activate only once each turn.

Llanowar Elves

Generous Ent

Reach
When Generous Ent enters, create a Food token. (It's an artifact with "{2}, {T}, Sacrifice this artifact: You gain 3 life.")
Forestcycling {1} ({1}, Discard this card: Search your library for a Forest card, reveal it, put it into your hand, then shuffle.)

You Meet in a Tavern

Choose one —
• Form a Party — Look at the top five cards of your library. You may reveal any number of creature cards from among them and put them into your hand. Put the rest on the bottom of your library in a random order.
• Start a Brawl — Creatures you control get +2/+2 until end of turn.

Lead the Stampede

Look at the top five cards of your library. You may reveal any number of creature cards from among them and put the revealed cards into your hand. Put the rest on the bottom of your library in any order.

Dwynen's Elite

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

Winding Way

Choose creature or land. Reveal the top four cards of your library. Put all cards of the chosen type revealed this way into your hand and the rest into your graveyard.

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.

Jaspera Sentinel

Reach
{T}, Tap an untapped creature you control: Add one mana of any color.

Timberwatch Elf

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

Avenging Hunter

Trample
When Avenging Hunter enters, you take the initiative.

Birchlore Rangers

Tap two untapped Elves you control: Add one mana of any color.
Morph {G} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Negate

Elvish Visionary

When Elvish Visionary enters, draw a card.

Nyxborn Hydra

Bestow {X}{G}{G} (If you cast this card for its bestow cost, it's an Aura spell with enchant creature. It becomes a creature again if it's not attached.)
Reach, trample
Nyxborn Hydra enters with X +1/+1 counters on it.
Enchanted creature gets +1/+1 for each +1/+1 counter on Nyxborn Hydra and has reach and trample.

Gorilla Shaman

{X}{X}{1}: Destroy target noncreature artifact with mana value X.

Priest of Titania

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

Masked Vandal

Changeling (This card is every creature type.)
When Masked Vandal enters, you may exile a creature card from your graveyard. If you do, exile target artifact or enchantment an opponent controls.

Wellwisher

{T}: You gain 1 life for each Elf on the battlefield.

Hallow

Prevent all damage target spell would deal this turn. You gain life equal to the damage prevented this way.