After defeating the Moldorm you enter this room, containing The Full Moon Cello, the first of eight Instruments of the Siren needed to wake the Windfish
Perspective view of the Tail Cave, click image for full size
Top down view of the Tail Cave, click image for full size.
I've made a post on gamedevs, looking for more programmers, I want to get a new beta out soon but that is just too much to ask of one programmer, hopefully it won't be too long of a wait.
Not sure what area to move to next.