Timberwatch Elf

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

Cultivator of Blades

Fabricate 2 (When this creature enters, put two +1/+1 counters on it or create two 1/1 colorless Servo artifact creature tokens.)
Whenever Cultivator of Blades attacks, you may have other attacking creatures get +X/+X until end of turn, where X is Cultivator of Blades's power.

Fyndhorn Elves

Elvish Mystic

Marwyn, the Nurturer

Whenever another Elf you control enters, put a +1/+1 counter on Marwyn, the Nurturer.
{T}: Add an amount of {G} equal to Marwyn's power.

Wirewood Symbiote

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

Beast Whisperer

Whenever you cast a creature spell, draw a card.

Arbor Elf

Imperious Perfect

Other Elves you control get +1/+1.
{G}, {T}: Create a 1/1 green Elf Warrior creature token.

Copperhorn Scout

Whenever Copperhorn Scout attacks, untap each other creature you control.

Viridian Joiner

{T}: Add an amount of {G} equal to Viridian Joiner's power.

Priest of Titania

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

Joraga Warcaller

Multikicker {1}{G} (You may pay an additional {1}{G} any number of times as you cast this spell.)
Joraga Warcaller enters with a +1/+1 counter on it for each time it was kicked.
Other Elf creatures you control get +1/+1 for each +1/+1 counter on Joraga Warcaller.

Elvish Archdruid

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

Elvish Harbinger

When Elvish Harbinger enters, you may search your library for an Elf card, reveal it, then shuffle and put that card on top.
{T}: Add one mana of any color.

Wirewood Lodge

{T}: Add {C}.
{G}, {T}: Untap target Elf.

Fauna Shaman

{G}, {T}, Discard a creature card: Search your library for a creature card, reveal it, put it into your hand, then shuffle.

Wood Elves

When Wood Elves enters, search your library for a Forest card, put that card onto the battlefield, then shuffle.

Elvish Champion

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

Sylvan Messenger

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
When Sylvan Messenger enters, reveal the top four cards of your library. Put all Elf cards revealed this way into your hand and the rest on the bottom of your library in any order.

Nissa, Who Shakes the World

Whenever you tap a Forest for mana, add an additional {G}.
+1: Put three +1/+1 counters on up to one target noncreature land you control. Untap it. It becomes a 0/0 Elemental creature with vigilance and haste that's still a land.
−8: You get an emblem with "Lands you control have indestructible." Search your library for any number of Forest cards, put them onto the battlefield tapped, then shuffle.

Eternal Witness

When Eternal Witness enters, you may return target card from your graveyard to your hand.

Wellwisher

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

Reclamation Sage

When this creature enters, you may destroy target artifact or enchantment.

Dwynen, Gilt-Leaf Daen

Reach (This creature can block creatures with flying.)
Other Elf creatures you control get +1/+1.
Whenever Dwynen attacks, you gain 1 life for each attacking Elf you control.

Llanowar Elves

Thunderfoot Baloth

Trample
Lieutenant — As long as you control your commander, Thunderfoot Baloth gets +2/+2 and other creatures you control get +2/+2 and have trample.

Lys Alana Huntmaster

Whenever you cast an Elf spell, you may create a 1/1 green Elf Warrior creature token.

Ezuri, Renegade Leader

{G}: Regenerate another target Elf.
{2}{G}{G}{G}: Elf creatures you control get +3/+3 and gain trample until end of turn.

Immaculate Magistrate

{T}: Put a +1/+1 counter on target creature for each Elf you control.

Sylvan Ranger

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

Path of Ancestry

Path of Ancestry enters tapped.
{T}: Add one mana of any color in your commander's color identity. When that mana is spent to cast a creature spell that shares a creature type with your commander, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Steel Leaf Champion

Steel Leaf Champion can't be blocked by creatures with power 2 or less.

Vivien, Champion of the Wilds

You may cast creature spells as though they had flash.
+1: Until your next turn, up to one target creature gains vigilance and reach.
−2: Look at the top three cards of your library. Exile one face down and put the rest on the bottom of your library in any order. For as long as it remains exiled, you may cast it if it's a creature spell.

Nykthos, Shrine to Nyx

{T}: Add {C}.
{2}, {T}: Choose a color. Add an amount of mana of that color equal to your devotion to that color. (Your devotion to a color is the number of mana symbols of that color in the mana costs of permanents you control.)