Halo 5 with the Arbiter, awsome, including the Flood. Oh hell yea. The Flood were a pain in the ***, but were a formitable foe. The promethians however, are a bunch of ********. With the addition of Forerunner weapons, holy f...ing christ, two damn steps and digitalized. Took my buddy and I awhile to get past both Coveies and promethians.
On another note, I can see it possible for the return of the Arbiter and the Flood, but it's 343i's choice whether to do so or not. Still I agree with Fred about bringing back both. When it comes to the Flood coming back, it should be within reason to bring the Flood back. Something that can make us as gamers go "SOB" yet laugh cause, it's gonna make the fight more difficult to survive through. Which makes us as gamers have to be quick on the controls and fast to pull the trigger.
(suggestion) Could it be possible to bring back dual weilding, and the surpressed smg/magnum.
The surpressed smg and surpressed magnum came in handy for stealth parts of the missions, which would be nice to when it comes to staying quite and hidden in case of needing to sneak by heavily gaurded areas. And for the dual weilding, well... it's just plan fun to go out guns blazing in campaign and multiplayer.