So, for those of you who have played Spartan ops and campaign, and are up to date on everything, you will understand this. *And If you haven’t read the Kilo two five series, then this explains why the elites are attacking again.
So, the elite Jul 'Mdama, he is a sanghili war criminal. He was locked away on ONYX. He hated how the arbiter sided with the Humans. Eventually, he escaped ONYX, and he leared that the arbiter shot down a cruiser with his wife, and his friend on it. While on ONYX, he learned that there was a forerunner locked away on a planet called Requiem. So, he assembles a fleet in search for a forerunner named The Didact.
So, I think he is going to try and assemble the Promethean and lead them to Sanghilios, and kill the arbiter and lead the sanghili. Once that’s done, he will then move on to earth.