John Garavaglia 
Wrath of the Titans [EPUB ebook] 
The Battle for Argos

Argus has been at peace for five years. Perseus has defeated the gorgon Medusa and slain the Kraken, assuming the throne. His people celebrate as he and his wife, Queen Andromeda expect their first born. But not everyone rejoices for the royal couple. The evil Calibus, once thought dead, has been released by Hades from the underworld. The Pretender has taken his bride, his position, and his favor of Zeus, and now he seeks to claim what is rightfully his own. And with news of a baby boy, he may do just that.