I have heard some rumors (not in the internet, otherwise I would give you a link):
on the legendary planet “Requium” can be some lost marines or other unsc/human forces. (They [some guys i know] said it was in a halo book or something); and they might be evil or fight against other humans / or against the infinity ppl.
I myself never have checked the halo books. I read other things 
// so iam not a hardcore halo fan.
So may be some one can help with this rumor?
May be these guys only want to kid me… but that will be very untypical for them.
It is probably just a false rumour. That said, I think that the addition of some rogue SPARTAN-IVs at some point in the trilogy as enemies could be an interesting twist, but the style in which AI marines fight would make them dull enemies to fight.
meh… i hoped for more replys of ppl who have readen the books…
Some humans were stranded on a Forerunner planet, but that Onyx and they were rescued. Apart from that I have heard nothing about lost UNSC or Insurrection forces that would be lost on a Forerunner planet and be hostile.
Are you speaking of the URF (United Rebel Front)?
I don’t think they’ll be in Halo 4. It would be interesting to fight humans though, without shields!
Why would humans try to kill Master Chief? O.o
At one point i had thought about MC and gang getting fed up with ONI (as shady as they are) and would oust them… or something.
> Some humans were stranded on a Forerunner planet, but that Onyx and they were rescued. Apart from that I have heard nothing about lost UNSC or Insurrection forces that would be lost on a Forerunner planet and be hostile.
yeah man, that can be the thing…
i remember… because months ago noone has known on which planet chief landed… and there was something about: it could be onyx.
Looks like my mates are not on the newest info stand.
> Why would humans try to kill Master Chief? O.o
There are a lot of CoD fans in this galaxy… :s
This sounds like quite the distortion. They could be talking about the ancient human culture.
In the time of the Forerunners, there were san’shyuum, sangheili, and human civilizations. The human one was attacked by the Flood and, in order to maintain the resources necessary to continue battling the Flood, invaded several Forerunner worlds. The humans and san’shyuum were allied, so the war that sparked between the Forerunners and the human-san’shyuum alliance was actually quite contested. But the humans were fighting two wars (the Forerunners and the Flood), so they crumpled quite quickly and in the last moments the San’shyuum betrayed them and abandoned to seek Forerunner mercy.
Humans were wiped out, but their memory and samples were preserved by a forerunner lifeshaper called the Librarian. She revived the species on a planet known as Erde-Tyrene (likely Earth), and altered their genes so that many of them carried the memories of ancient human culture, as well as special abilities or senses related to Forerunner technology.
This is what we know of them, but it’s possible that there was at least a small faction of ancient humans that retreated beyond the reach of the Forerunners (either during or after the war), and survived beyond the edge of the galaxy. It could be their ship that crashed into Installation 04 (according to Halo: Anniversary). They could be a very different people that seek revenge on the Forerunners and dominance over anything that remains in the galaxy.
As an added piece of suspicious information, over the past two Forerunner books we’ve gotten a versatile array of human species that are all the result of Forerunners altering the evolution of the species in places. There are smaller humans, larger humans, narrower humans, wider humans, ect. Which sounds like the kind of story structure you’d implement if you wanted to make an enemy faction that had varying body shapes and sizes to keep a player visually engaged while fighting them (like the Covenant).