User blog comment:Hyperborean/"The House of Hades" – official expectations blog/@comment-153.107.97.161-20121026024143/@comment-5112532-20121026190920

I think you mean 'breath'? Haha.

I don't think Nico would sacrifice himself, I think it would be Percabeth have a little argument about who will do it, before the decide the doors open from the mortal world and they meet the other demigods.

Yeah, I think that Frank will be the one to sacrifice himself, or Leo, those two seem to be the most likely choice. (This sounds bad) BUT it will clear up the love triangle between Frank, Hazel and Leo.