From the back of the book:
Encyclopedia: Netherworld details two major iconic features of Eana: its underground world, the Netherworld, and its most dangerous foe, Canker. Within, you will find out about their history, their secrets, and related magic items.
Netherworld. Explore the subterranean lands beneath the Free City, the Drakenbergen, the Septentrion, Kaan, and adjoining seas! Delving into dark tunnels, discover lives and cultures radically different from the surface’s. Adventures will feature urban schemes in cities of below, and perilous voyages into niyerdae—wild lands in perpetual darkness.
Atmospheres. Depending on the locale, adventures will evoke twilit wonder, dark fantasy, games of thrones, or science fantasy. Choose your own Netherworld!
Canker. A major antagonist, Canker is a complex entity, simultaneously a plane, a godlike power, and a life form. Magic items, fully fleshed-out cities, cultists... All you need to play a campaign giving pride of place to this terrifying threat!
Campaign Material. Contents feature more than 120 magic items, including fell blasphemies filled with Canker’s deleterious energy and glyphs that can alter the environment of subterranean regions. New options are also provided for the creation and evolution of adventurers.
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