Wirewood Pride

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

Lys Alana Huntmaster

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

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

Choose a creature type. You gain 2 life for each permanent you control of that type.

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

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