Used book - Percy Jackson - Book 2 - The Sea of Monsters, Rick Riordan, Mona de Pracontal

When a simple soccer game turns into a battle against a gang of giant cannibals, Percy the demigod has a terrible premonition. As his strange nightmares foretold, the magical borders protecting Camp Half-Blood are being poisoned. To save their home, Percy and his friends will have to travel through the Sea of Monsters, which lives up to its name.