Ulvenwald Observer

Whenever a creature you control with toughness 4 or greater dies, draw a card.

Birds of Paradise

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.

Selesnya Signet

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 enters, if it was kicked, create X 1/1 green Saproling creature tokens.

Timber Protector

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

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.

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.

Seedguide Ash

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

Golgari Signet

Path to Exile

Exile target creature. Its controller may search their library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Magnigoth Treefolk

Domain — For each basic land type among lands you control, this creature has landwalk of that type. (It can't be blocked as long as defending player controls a land of that type.)

Orchard Warden

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

Indomitable Ancients

Black Poplar Shaman

Sapling of Colfenor

Indestructible
Whenever Sapling of Colfenor attacks, reveal the top card of your library. If it's a creature card, you gain life equal to that card's toughness, lose life equal to its power, then put it into your hand.

Kodama's Reach

Wormwood Treefolk

{G}{G}: This creature gains forestwalk until end of turn and deals 2 damage to you. (It can't be blocked as long as defending player controls a Forest.)
{B}{B}: This creature gains swampwalk until end of turn and deals 2 damage to you. (It can't be blocked as long as defending player controls a Swamp.)

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.

Murmuring Bosk

({T}: Add {G}.)
As this land enters, you may reveal a Treefolk card from your hand. If you don't, this land enters tapped.
{T}: Add {W} or {B}. This land deals 1 damage to you.

Bosk Banneret

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

Ironroot Treefolk

Swords to Plowshares

Exile target creature. Its controller gains life equal to its power.

Faeburrow Elder

Vigilance
This creature gets +1/+1 for each color among permanents you control.
{T}: For each color among permanents you control, add one mana of that color.

Deadwood Treefolk

Vanishing 3 (This creature enters with three time counters on it. At the beginning of your upkeep, remove a time counter from it. When the last is removed, sacrifice it.)
When this creature enters or leaves the battlefield, return another target creature card from your graveyard to your hand.

Argothian Treefolk

Prevent all damage that would be dealt to this creature by artifact sources.

Orzhov Signet

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.

Doran, the Siege Tower

Each creature assigns combat damage equal to its toughness rather than its power.

Indatha Triome

({T}: Add {W}, {B}, or {G}.)
This land enters tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)