Poseidon : Earth Shaker
After defeating their father and sending him down into a crater that reaches far below the Earth's crust, Poseidon and his brothers are faced with the decision of who will rule which realm.
Hades gets the Underworld. Zeus claims the Heavens. And Poseidon is left with the Sea.
It seems like a good fit. As God of the Sea, Poseidon has quite a bit of power over man without having to be bothered with him much, except when a female catches his eye.
Sadly, despite trying to have children who can continue his line, his children are all monstrous. When they are ugly, they can be kind, but turn cruel when cruelly treated (Polyphemus the Cyclops). And even when they are gorgeous, they can be monstrously cruel (Theseus).
Poseidon's attempts to deal with man never seem to end up right. There is death, destruction, and horror left wherever he and his children go.
But Poseidon won't let anyone mess with him or his children and those who remember that are the ones who will survive.
Final thoughts: This was not his best. Like his book on Hera, things are just getting far too confused. Granted, that's true for all Greek mythology. There's also not enough information about Poseidon for O'Connor to work with, so he ends up talking about the children, their quests, and their dealings with other people on quests. Odysseus gets a chunk of the book, as does Theseus. The artwork is still absolutely amazing and the series is still good for getting people hooked on Greek mythology, so it's definitely worth the look.