Deep in tang men base there is a ca

Deep in tang men base there is a cave called the snake cave. In the far end of the cave is a pool past the giant snake skeleton. At the bottom of the pool is a chest that spawns every day once at around 1400-1700. Get the item from the chest then take that to the legendary medicine man to the west of the entrance. Give him that item. You might be attacked by a random bandit on the way but he's no big deal.