From publisher blurb: A distant, cosmic melody fills the twilight-tinged skies, blending pleasantly into the ambient noise rising up from the bustling streets. Merchants haggle loudly with patrons as strange and varied as the goods hanging from their stalls as cries of triumph and defeat ring out from the packed arena, nearly drowning out the sounds of music and revelry coming from the adjacent house of entertainment. This is Witch Tree, the Hidden Plane. A hot spot of travel for those with the right connections, anything that an offbeat caster desires can be found within the boundaries of Witch Tree. Whether that be tutelage in the eldritch arts, a rare alchemical component, or simply a good place to blow off steam without worrying about disconcerting the locals, Witch Tree is the peculiar haven that warlocks dream of. This supplement includes: The origins of Witch Tree, the Hidden Plane. Points of interest around Witch tree. Important NPCs from the plane. Maps of the plane plus variant maps for the Eldritch Theater, an illusionary arena within Witch Tree. New warlock-specific spells. New illicit boons. New harvestable materials.