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

I have an idea to how Posiedon or Neptune can appear maybe the demigods on the Argo 2 ask for  safe paasage and if it is Posiedon he would let them go but they have to do a quest because of a ancient law if Neptune is like  Minerva then he will force them into the quest to get payback against the Romans. The quest could be to kill that giant turtle.