List of characters in the Camp Half-Blood series
Typhon - A very powerful monster. He sired many monsters by Echidna. He lives and sleeps inside Mount Saint Helens. Percy is such a powerful demigod that he almost wakes Typhon during his visit there. In The Last Olympian, he awakes and moves across America and destroys everything in his path. Due to him being concealed in mist, Typhon's appearance is not described and appears as a freak storm. The gods of Olympus try to stop him, but he is too powerful. In the end, Poseidon and his army help defeat him where Poseidon opened up a tunnel that sent Typhon into Tartarus. Once Typhon was defeated, a wave of Venti were born.