User blog comment:Hermione Chase/"The Blood of Olympus" Expectations/@comment-4555714-20131019100145

To storm or fire the world must fall: It's been suggested that "fire" refers to Leo or Frank. Given the choice between the two of them, I think it refers to Frank. Reason: Leo's fire powers were useless against the giant Clytius. If normal fire does not work against a giant, how will it work against the Earth, Gaea? A normal fire could not melt he chains of Thanatos, but Frank's "fire of life" could. And Frank's fire is a sacrifice, which is a more powerful thing than force, at least in PJatO world. Luke ended Krono's return with one stab. Despite all of his powers, Kronos depended on one mortal body, and on the will of one mortal's soul.

As for the comparison of Fire to Storm? I have no clue.

Except, there was a hint in HoH, wasn't there? The horses--wind spirits. Jason had to choose between storm and fire: the spirits were made partly of storm, partly of fire. I guess fire represented the Greeks, storm the Romans. And since he chose CHB over CJ, the horses took the form of fire instead of storm. (Did I get all that right?) And he is no longer Roman, which even the dead Romans recognized.

Idk what that has got to do with defeating Gaea though