Forest

Scale Up

Until end of turn, target creature you control becomes a green Wurm with base power and toughness 6/4.
Overload {4}{G}{G} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Thrill of Possibility

As an additional cost to cast this spell, discard a card.
Draw two cards.

Stomping Ground

({T}: Add {R} or {G}.)
As Stomping Ground enters, you may pay 2 life. If you don't, it enters tapped.

Minion of the Mighty

Menace
Pack tactics — Whenever Minion of the Mighty attacks, if you attacked with creatures with total power 6 or greater this combat, you may put a Dragon creature card from your hand onto the battlefield tapped and attacking.

Infuriate

Target creature gets +3/+2 until end of turn.

Atarka, World Render

Flying, trample
Whenever a Dragon you control attacks, it gains double strike until end of turn.

Tormenting Voice

Werewolf Pack Leader

Pack tactics — Whenever Werewolf Pack Leader attacks, if you attacked with creatures with total power 6 or greater this combat, draw a card.
{3}{G}: Until end of turn, Werewolf Pack Leader has base power and toughness 5/3, gains trample, and isn't a Human.

Terror of Mount Velus

Flying
Double strike (This creature deals both first-strike and regular combat damage.)
When this creature enters, creatures you control gain double strike until end of turn.

Rootbound Crag

Rootbound Crag enters tapped unless you control a Mountain or a Forest.
{T}: Add {R} or {G}.

Hobgoblin Captain

Pack tactics — Whenever Hobgoblin Captain attacks, if you attacked with creatures with total power 6 or greater this combat, Hobgoblin Captain gains first strike until end of turn.