This is why I think they've been coined as "the darkeness". When people speak of the darkeness, they don't speak of this rolling black cloud of pestilence that kills all in it's wake, I'm thinking it's literally these ships and because of they're size and lack of comprehension, all they know is it gets dark when they invade, due to some pretty intuitive tactics. Their invasion tactic, in my opinion, has always been like this: 1. Send a smaller ship to scout. 2. Confirm. 3. Mothership invades during the day, parking really close to the planet's surface, blocking out all light. 4. Send in the attack ships during the hysteria to decimate life, take no prisoners. They don't strike me as a species/entity that loots, so I doubt any of our tech would go missing. When the time comes to fight these things, I only hope that Bungie gives it more justice than a Ghaul, or Xol fight..