User blog comment:Hyperborean/"The House of Hades" – official expectations blog/@comment-4902593-20130222110128

Some users think that when Rick says "some scenes from Tartarus" he would be reffering to dreams or images. If that was the case then Percy or any other demigod would already know that Nico was in Tartarus. No, dreams and images certainly don't work in Tartarus. So obviously it would be Percy or Annabeth's POV. P.S. Does Gaia know what's going on in Tartarus?