It's the War Priest!!!! Kill him. He's in a raid so all we do is shoot him a bunch until he dies. That's the whole purpose of it right? To constantly shoot enemies who are just visiting our solar system. At least there was a crazy story behind Vault of Glass. I probably spent 12 Hours of game play trying to uncover secret hidden things in The Vault...I didn't really discover anything other than one of the hidden chests.