I loved this episode, and not just because it involved a volcano :-)
I've been hoping we'd learn more about the red light in the iwakura for some time, and now we've got it in a huge, thrilling, dose. The visions conjured up by the description are vivid, dramatic and frightening. Through the vision, I've learnt a lot more about the ancient power of the kami, so for me this episode is one of the best.