Fungal Sprouting

Create X 1/1 green Saproling creature tokens, where X is the greatest power among creatures you control.

Seedguide Ash

When Seedguide Ash dies, you may search your library for up to three Forest cards, put them onto the battlefield tapped, then shuffle.

Kalonian Twingrove

Kalonian Twingrove's power and toughness are each equal to the number of Forests you control.
When Kalonian Twingrove enters, create a green Treefolk Warrior creature token with "This creature's power and toughness are each equal to the number of Forests you control."

Timber Protector

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

Reach of Branches

Create a 2/5 green Treefolk Shaman creature token.
Whenever a Forest you control enters, you may return Reach of Branches from your graveyard to your hand.

Naturalize

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.
Dauntless Dourbark has trample as long as you control another Treefolk.

Orchard Warden

Whenever another Treefolk creature you control enters, you may gain life equal to that creature's toughness.

Cloudcrown Oak

Reach (This creature can block creatures with flying.)

Lignify

Enchant creature
Enchanted creature is a Treefolk with base power and toughness 0/4 and loses all abilities.

Return to the Earth

Destroy target artifact, enchantment, or creature with flying.

Dungrove Elder

Hexproof (This creature can't be the target of spells or abilities your opponents control.)
Dungrove Elder's power and toughness are each equal to the number of Forests you control.

Fists of Ironwood

Enchant creature
When Fists of Ironwood enters, create two 1/1 green Saproling creature tokens.
Enchanted creature has trample.

Verdeloth the Ancient

Kicker {X} (You may pay an additional {X} as you cast this spell.)
Saproling creatures and other Treefolk creatures get +1/+1.
When Verdeloth the Ancient enters, if it was kicked, create X 1/1 green Saproling creature tokens.

Cultivate

Search your library for up to two basic land cards, reveal those cards, put one onto the battlefield tapped and the other into your hand, then shuffle.

Rampant Growth

Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Forest

Bosk Banneret

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

Everbark Shaman

{T}, Exile a Treefolk card from your graveyard: Search your library for up to two Forest cards, put them onto the battlefield tapped, then shuffle.

Ghastbark Twins

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
Ghastbark Twins can block an additional creature each combat.