Once you accept this quest, you can begin searching each pool of water in B3F of the Lush Woodlands. Most of the time you will find nothing; occasionally you may find items like Medicas. The ring is located in the pool of water at C-6/3-2. If you need to get around the Bloodbear guarding that area, use the shortcuts that you have previously opened to sneak behind the Berserker King.