The Cerulean Coast is one of the areas in Shadow of the Erdtree that can be accessed through Charo's Hidden Grave. The area is filled with mesmerizing blue flowers and stone coffins that serve as an access point to one of the NPC's questlines. This guide includes a step-by-step walkthrough on how to reach Demi-Human Queen Marigga and how players can defeat her to obtain the rare Katana.