Halo 5 Trailer: References from the books?

So, I just watched the Halo 5 Trailer. The first thing that caught my eye was the fact that the robed figure (Master Chief), was following stones, just like how Bornstellar described the stone-placing methods of the ancient humans in the cryptum. Another thing I noticed was the Forerunner robot (War Sphinx/Seeker?) rose out of a circular hole not too different from a “dazzler”. (Another one of Bornstellar’s observations. Dazzlers were supposed to make a relic of importance, such as a cryptum, not very noticeable.) And finally, I saw dead robed figures on the ground. Perhaps other humans? Surviving Forerunners? A new/old race? (Jjaro, anyone?) If anyone knows more about this, or wants to correct any mistakes I might have made, feel free to post!

Hmm… Forgot about the stone thing. Interesting observations. I didn’t seem to notice any more dead people though.