Board Thread:The B&B/@comment-4803039-20150113210347/@comment-4803039-20150114231943

Riordan has a thing for having the modern heroes changing/breaking the cycle. In 'House of Hades' they convince the giant Damasen to break the cycle he was caught in and make his own fate.

There's also the option of the Demigods somehow turning them to stone.