the speaker is the darkness who in fact is emperor palpatine traveler is the death star and xur is lord vader. and we so called guardians with our chatterwhites are the 501st legion fighting against those that wont submit to the empire. for example the remnants of the separatists and there vex droids. and for some weird reason also space marines from the Imperium of Man i mean cabal. post your own theorys in the comment section would love to hear them.