Utopia Mycon

At the beginning of your upkeep, put a spore counter on Utopia Mycon.
Remove three spore counters from Utopia Mycon: Create a 1/1 green Saproling creature token.
Sacrifice a Saproling: Add one mana of any color.

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."

Lumberknot

Hexproof (This creature can't be the target of spells or abilities your opponents control.)
Whenever a creature dies, put a +1/+1 counter on Lumberknot.

Sporoloth Ancient

At the beginning of your upkeep, put a spore counter on Sporoloth Ancient.
Creatures you control have "Remove two spore counters from this creature: Create a 1/1 green Saproling creature token."

Rootgrapple

Destroy target noncreature permanent. If you control a Treefolk, draw a card.

Sporemound

Landfall — Whenever a land you control enters, create a 1/1 green Saproling creature token.

Bosk Banneret

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

Orchard Warden

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

Fangorn, Tree Shepherd

Treefolk you control have vigilance.
Whenever one or more Treefolk you control attack, add twice that much {G}.
You don't lose unspent green mana as steps and phases end.

Evolution Sage

Landfall — Whenever a land you control enters, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Psychotrope Thallid

At the beginning of your upkeep, put a spore counter on Psychotrope Thallid.
Remove three spore counters from Psychotrope Thallid: Create a 1/1 green Saproling creature token.
{1}, Sacrifice a Saproling: Draw a card.

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.

Life and Limb

All Forests and all Saprolings are 1/1 green Saproling creatures and Forest lands in addition to their other types. (They're affected by summoning sickness.)