In the epic conclusion to the 5 Worlds series, the final battle looms as Oona, Jax, and An Tzu travel to the treacherous world of Grimbo (E)! There, Oona must light the last beacon to save the 5 Worlds, but first she has to find it! When Jax saves an old friend, Oona is given a clue to the green beacon's location. Unfortunately, the journey to lighting it on this strange, watery planet is the most dangerous yet. Meanwhile, Stan Moon has one more trick...