Primeval Herald

Trample
Whenever Primeval Herald enters or attacks, you may search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Ivy Lane Denizen

Whenever another green creature you control enters, put a +1/+1 counter on target creature.

Band Together

Up to two target creatures you control each deal damage equal to their power to another target creature.

Forest

Elvish Warmaster

Whenever one or more other Elves you control enter, create a 1/1 green Elf Warrior creature token. This ability triggers only once each turn.
{5}{G}{G}: Elves you control get +2/+2 and gain deathtouch until end of turn.

Elvish Rejuvenator

When Elvish Rejuvenator enters, 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.

Might of the Masses

Target creature gets +1/+1 until end of turn for each creature you control.

Dwynen's Elite

When this creature enters, if you control another Elf, create a 1/1 green Elf Warrior creature token.

Reckless Amplimancer

{4}{G}: Double Reckless Amplimancer's power and toughness until end of turn.

Reclamation Sage

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

Thriving Grove

Thriving Grove enters tapped. As it enters, choose a color other than green.
{T}: Add {G} or one mana of the chosen color.

Elven Bow

When Elven Bow enters, you may pay {2}. If you do, create a 1/1 green Elf Warrior creature token, then attach Elven Bow to it.
Equipped creature gets +1/+2 and has reach.
Equip {3}

Elderleaf Mentor

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

Roots of Wisdom

Mill three cards, then return a land card or Elf card from your graveyard to your hand. If you can't, draw a card. (To mill a card, put the top card of your library into your graveyard.)