Immaculate Magistrate

{T}: Put a +1/+1 counter on target creature 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.

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.

Llanowar Elves

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.

Priest of Titania

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

Elvish Mystic

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.

Boreal Druid

Wellwisher

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

Elvish Archdruid

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

Beast Whisperer

Whenever you cast a creature spell, draw a card.

Timberwatch Elf

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

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.

Elvish Champion

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

Lys Alana Huntmaster

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

Wirewood Channeler

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

Imperious Perfect

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