This is a Side Quest in the Orient (Act III). Shortly after leaving the City of Chang'an for the first time, you'll enter the Quinba Bamboo Forest. Talk to Rang Ju twice (arrow in the first picture), then enter the cave through either of the two entrances (circles in the first picture). The quest is completed as soon as you reach the three mahogany chests (cross in the second picture).
- Experience: 26k / 65k / 180k (normal / epic / legendary)
- (the loot from the chests)