Ahh Very interisting.
Their are actually some interisting possibilities with halo 4;
we may just see some surviving forerunners (forgive me for any miss spelled words )
REMEMBER!!!!! NOT ALL forerunners were killed
They had SHIELD WORLDS to protect variouse species (and quite possibly, them selves)
But we may (GOD WHY?!!??!!) once again meet the flood
But possibly the biggest of all, SOMETHING INTIRELY differint
All we know so far is that it is a "Ancient Threat"
Now hear me out, the Forerunners dissapeared, so they may still be alive, although it may not be.
I believe the idea that it may be forerunners has a FAIR chance, now that DOES NOT mean I think its a 100% chance, I just thing theirs a chance. Now, the reason the forerunners may not have stopped the whole Human-Covie war may have simply been becouse (this may sound ridiculouse, but here it goes) they were TRAPPED. If you have read Ghost of Onyx (now I havent read the secound) you will know that once the group was inside the planet, they coundnt get OUT! Now, you may find it ridicuoulouse but its possible
I would Write more but its rather late, so thats all i have to say for know
THIS HAS BEEN A MESSAGE FROM A VERY Evil Engineer