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

Whenever another green creature enters the battlefield under your control, put a +1/+1 counter on target creature.

Alliance — Whenever another creature enters the battlefield under your control, Attended Socialite gets +1/+1 until end of turn.

{T}: Until end of turn, target Forest becomes an X/X Treefolk creature in addition to its other types, where X is the number of Elves you control.

Reach (This creature can block creatures with flying.) Whenever Ezuri's Archers blocks a creature with flying, Ezuri's Archers gets +3/+0 until end of turn.

When Galadhrim Guide enters the battlefield, scry 2.

Vigilance (Attacking doesn't cause this creature to tap.)

Reach Whenever High-Rise Sawjack blocks a creature with flying, High-Rise Sawjack gets +2/+0 until end of turn.

Reach (This creature can block creatures with flying.) Fabricate 1 (When this creature enters the battlefield, put a +1/+1 counter on it or create a 1/1 colorless Servo artifact creature token.)

Trample Revolt — Lifecraft Cavalry enters the battlefield with two +1/+1 counters on it if a permanent you controlled left the battlefield this turn.

Whenever another creature enters the battlefield under your control, Llanowar Stalker gets +1/+0 until end of turn.

Vigilance, trample

Reach

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

Dash {1}{G} (You may cast this spell for its dash cost. If you do, it gains haste, and it's returned from the battlefield to its owner's hand at the beginning of the next end step.) Whenever Treetop Ambusher attacks, target creature you control gets +1/+1 until end of turn.

Protection from Goblins

Whenever Wildwood Tracker attacks or blocks, if you control another non-Human creature, Wildwood Tracker gets +1/+1 until end of turn.

Vigilance {5}{G}, {T}: Draw a card. This ability costs {1} less to activate for each +1/+1 counter on creatures you control.

When Elvish Visionary enters the battlefield, draw a card.

When Entourage of Trest enters the battlefield, you become the monarch. Entourage of Trest can block an additional creature each combat as long as you're the monarch.

When Llanowar Empath enters the battlefield, scry 2, then reveal the top card of your library. If it's a creature card, put it into your hand. (To scry 2, look at the top two cards of your library, then put any number of them on the bottom of your library and the rest on top in any order.)

Sacrifice Elvish Eulogist: You gain 1 life for each Elf card in your graveyard.

Whenever another creature enters the battlefield, you gain 1 life.

{T}: Untap target Forest.

Deathtouch {T}: Add one mana of any color.

{T}: Add {G}.

When Elvish Pioneer enters the battlefield, you may put a basic land card from your hand onto the battlefield tapped.

When Elvish Rejuvenator enters the battlefield, look at the top five cards of your library. You may put a land card from among them onto the battlefield tapped. Put the rest on the bottom of your library in a random order.

When Farhaven Elf enters the battlefield, you may search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

{T}: Add {G}.

{T}: Create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

{T}, Sacrifice Llanowar Druid: Untap all Forests.

{T}: Add {G}.

{T}: You may put a land card from your hand onto the battlefield.

When Llanowar Visionary enters the battlefield, draw a card. {T}: Add {G}.

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

When Springbloom Druid enters the battlefield, you may sacrifice a land. If you do, search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.

When Sylvan Ranger enters the battlefield, you may search your library for a basic land card, reveal it, put it into your hand, then shuffle.

Reach Whenever you cast an Elf spell, you may have Lys Alana Bowmaster deal 2 damage to target creature with flying.

{T}: Scattershot Archer deals 1 damage to each creature with flying.

Deathtouch

Gathered Swarm — Whenever one or more tokens enter the battlefield under your control, put a +1/+1 counter on Cloakwood Swarmkeeper.

When Elderleaf Mentor enters the battlefield, create a 1/1 green Elf Warrior creature token.