From publisher blurb:
The adventure begins as an evil tribe of snakemen have begun to spread among the land, terrifying neighbouring towns. Nearby forests and waters have become poisoned and toxic, prompting hunters and druids to attempt to determine the source. In truth, a medusa named El’xythal and her minions have desecrated an ancient shrine, transforming it into a vile place known as Zy’ial Rammoun — The Serpentfang Fortress.
This adventure is split up into three possible encounters with three different “bosses” to defeat — the Giant Adder plaguing the forests surrounding the Serpentfang Fortress; the venomous Commander Nevarys (•nuh-vah-riss) who readies the snakemen warriors to invade a nearby village; and finally the medusa El’xythal who pulls the strings behind everything from her tainted shrine. These encounters can be played individually, sequentially as a mini-campaign which will take multiple sessions to complete, or as part of an ongoing recurring sidestory in your campaign, where the players can piece together the mystery of the poisoned forests and Serpentfang Fortress over multiple individual sessions.