Had something with a hook holding demigod... However, for a water-based demi-god, a hook makes sense and a reference to fishing. All other elements are common in water-based adventures. Guy needs to get a life or collaborate with Disney

A little dramatic, but it does answer, "weren't they bored for hundreds of years?" I've wondered what they were doing, as training and manipulating aren't evil enough. Controlling a criminal empire is also what Maul did. We got this hint before now...