A rather short but combat focused chapter so bring plenty of food or stamina royals for the building. Once you get the key you will be locked inside it in a dungeon like building. There are many weapons to help up until the final boss. in the storage area there are a couple of things to help fight him so make use of them. Use any weapons you have as well to help take him down. Once you final defeat him in his 2nd form, watch the following cutscene for the end of the chapter.