This is the Ritual training room inside the palace of mira.
used by the queen of Mira and the King of Mira to train they leave people inside the room to train hard in there mira fighthing way.
the ritual room has mirrors on the wall and statues along the walls, and in the middle of the room is a raised platform and in the middle of the platform is a alter made of the same material the mirrors are made from, in the middle of the alter is a book, The Book of Rituals and there is a key hole in the middle of the alter that is where that dagger