User blog comment:Hyperborean/"The House of Hades" – official expectations blog/@comment-4430596-20130705160221

So, here's a list of the Giants who haven't appeared yet and who they were killed by in Greek myths. I'm using it to try to guess who will appear in HoH


 * Eurytus (Dionysus)
 * I don't think he will appear as there has already been a bane of Dionysus.


 * Clytius (Hecate)
 * I doubt him too since Hecate isn't a major god.


 * Mimas (Hephaestus)
 * This seems likely since Leo is an important demigod and there hadn't been a bane of Hepaestus


 * Pallas (Athena)
 * Doubtful since Athena already has a bane.


 * Hippolytus (Hermes)
 * This seems plausable since we haven't really seen Hermes much this series.


 * Gration (Artemis)
 * This also seems plausable since Artemis is an important goddess who has been absent from HoO


 * Agrius & Thoas (Fates)
 * To me, the idea of the bane of the Fates seems very interesting, but I don't think Rick will use it.

So, we all know Porphyrion will appear, but for the rest of the giants, I think the most likely are Gration, Hippolytus, and Mimas. Obviously, I could be completely wrong, but those make the most sense to me.