From publisher blurb:
A keening gale tears across the Bitter Sea, parting the clouds above to unveil a turgid crimson moon. Ominous rumbling resounds from the churning waters below. The surface of the sea boils and bubbles like a witch’s cauldron—its waves foaming and swelling like a suppurating sore until a mass of jagged black rock erupts from the lightless depths. The Forlorn Isle has risen. Legend claims the small island holds the tomb of an ancient king whose crimes were so heinous his name was stricken from history. After his death, the weight of his evil deeds caused the isle to sink into the Bitter Sea.
But once every year, when the Blood Moon casts its baleful gaze upon the world, the cold brine rejects its cursed burden and the Forlorn Isle rises again, eagerly awaiting fresh victims. Despite the impressive tally of adventurers lost to the basalt bowels of the so-called Death King’s ruined keep, many brave souls have sailed there over the years, drawn like moths to a flame by legends of lost ancient treasure. When dawn breaks, the bleak island sinks into the deep once more, entombing alive those who would steal its sinister secrets.