Inspector Sinai:
There are 4 chaotic Sprites. If you defeat them in a certain order, their powers will revert to their former stable state.
Inside, you will also meet our inspectors. They are superior enchanters, and they will certainly help you if you need it.
You should know that the power of this sword is not yet complete; you will need a Sprite's help to strengthen it to its full potential. The book contains instructions about how to do that.
Finally, the fish in the temple may provide useful items. I recommend you catch them if you can!