Candon Shaman of the Dark Fen

From publisher blurb: The islanders fear some dark power has corrupted the Candon lizardmen of the lowland fens. If their shaman leader has fallen to the side of darkness, it is only a matter of time before his calls for war are answered by the fern goblins. Can the adventurers stop the shaman before his summons can be answered? This mini-adventure sets up certain events of Folio #14, and is for characters levels 1-3 in both 1E and 5E formats.