A One-Round Living Greyhawk Theocracy of the Pale Regional Adventure
From the introduction:
An ancient forest beckons with its eerie glow. Creatures lurk in the verdant canopy above, waiting for an unfortunate soul to pass by. Around each bend and from behind each fallen log, eyes peer through the mist. And below, the roots hold fast in their tangled tapestry.
An adventure for [character levels] 4 - 12.