Viridescent Wisps

Target creature becomes green and gets +1/+0 until end of turn.
Draw a card.

Dauntless Dourbark

Dauntless Dourbark's power and toughness are each equal to the number of Forests you control plus the number of Treefolk you control.
This creature has trample as long as you control another Treefolk.

Unstoppable Ash

Trample
Champion a Treefolk or Warrior (When this enters, sacrifice it unless you exile another Treefolk or Warrior you control. When this leaves the battlefield, that card returns to the battlefield.)
Whenever a creature you control becomes blocked, it gets +0/+5 until end of turn.

Nature's Lore

Search your library for a Forest card, put that card onto the battlefield, then shuffle.

Bosk Banneret

Treefolk spells and Shaman spells you cast cost {1} less to cast.

Explore

You may play an additional land this turn.
Draw a card.

Battlewand Oak

Whenever a Forest you control enters, this creature gets +2/+2 until end of turn.
Whenever you cast a Treefolk spell, this creature gets +2/+2 until end of turn.

Leaf-Crowned Elder

Kinship — At the beginning of your upkeep, you may look at the top card of your library. If it shares a creature type with this creature, you may reveal it. If you do, you may play that card without paying its mana cost.

Treefolk Harbinger

When this creature enters, you may search your library for a Treefolk or Forest card, reveal it, then shuffle and put that card on top.

Forest

Timber Protector

Other Treefolk creatures you control get +1/+1.
Other Treefolk and Forests you control have indestructible.