User blog comment:Hyperborean/"The House of Hades" – official expectations blog/@comment-5247339-20130622090134/@comment-3146930-20130622202138

I still think it is weird that Poseidon/Neptune has had nothing more then a mention so far in the series. I mean even Jupiter helped Jason defeat the first Gigantes and Pluto appears in Hazel's flashback, as well as ignoring her so she can stay alive. He even (possibly) aided her by sending Arion to guide her in the first chapter of HoH.