He heavily implied that the Arbiter and his co-conspirators will return in Halo 5. He's basically teasing everyone like 343i did pre-Halo 4. I'm curious as to how the mysterious race from the Halo CEA Terminal 5 and the ONI Prowler Rubicon/343GS plays into this. The Infinity will almost certainly have a large part to play, as well as the MC/Cortana relationship. I wonder if we get the chance to fight the Insurrection for the first time in a Halo campaign...