The four legendary kingdoms by Matthew Reilly

Jack West Jr. bk 4. Macmillan, 2016. ISBN 9781743534953
(Age: Secondary) Recommended. Fantasy. Jack West is called into Pine Gap, the secret US base in outback Australia where he is told about a runaway galaxy hurtling through space coming straight for Earth and the Milky Way Galaxy. Jack West's adopted daughter Lily, Alby and Sky Monster and his two dogs are kidnapped and taken to a remote and secret location where Jack must fight to the death in a restaging of the Tasks of Hercules. Under the auspices of Hades, King of the Underworld, Jack and fifteen others are pitted against one another and only one will survive. Jack is at a disadvantage because he is one of the few who doesn't actually realise why he is there. Others have been training and have been well prepared for the contest.
Each contestant has a group of hostages to ensure that they give their all. Each contest becomes more difficult and dangerous as each stage proceeds.
The winner of each contest gains a golden orb which when placed in its correct position within the arena, transmits signals to the rogue galaxy, which proves there is still intelligent life on earth.
The odds are stacked against Jack with Hades' own son being one of the contestants, and who is able to gain unfair advantages in his father's realm.
Jack's knowledge of the ancient world and its myths and legends proves invaluable, giving him the leverage he needs to overcome his opponents despite all odds.
The readers of Reilly's books involving the heroic Jack West will be familiar with the engaging cast of characters and the lengths they go to survive and be more than satisfied that the ending sets up another book to follow.
Mark Knight