The magical rainbow staircase has always been the only known path between the Upper World and the secret land of Droon. Or so you thought. Everything changes when Emperor Ko launches a massive, surprise attack on Zorfendorf Castle. This mighty fortress is hiding a legendary secret known as the Fifth River, a hidden passage that leads directly to the Upper World. Emperor Ko and his terrifying beasts will stop at nothing to capture the river and bring their dark magic to your home. You must join forces with Eric, Julie, Neal, and Princess Keeah as they rush to defend the castle. Together, you will dive deep beneath the ancient stone walls to solve a thrilling mystery and uncover the truth behind the Fifth River. Can you outsmart Ko and his monstrous army before they break through? Grab your courage and prepare for an epic battle to protect both worlds.