Wellwisher

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

Forest

Timberwatch Elf

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

Moment's Peace

Prevent all combat damage that would be dealt this turn.
Flashback {2}{G} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Priest of Titania

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

Glistener Elf

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

Taunting Elf

All creatures able to block Taunting Elf do so.

Rancor

Enchant creature
Enchanted creature gets +2/+0 and has trample.
When Rancor is put into a graveyard from the battlefield, return Rancor to its owner's hand.

Llanowar Elves

Elvish Visionary

When Elvish Visionary enters, draw a card.

Untamed Might

Target creature gets +X/+X until end of turn.