I forgot to answer the main post, the rebels (from the novels) seem to be more secretive than aggressive to the UNSC, as they don't really have anything to take on the UNSC and mainly bluff and hide (the UNSC don't destroy the rebels for some reason, they know of their existance though) like i said, they're mainly criminals and the sort rather than a full fledged rebel force, and as the game revolves around the covenant war there probaly won't be much attention on the rebels
And the covenant are at war with humans as a race, not just the UNSC, so they may manipulate rebels into a situation with the UNSC, but they wouldn't properly use them as a fighting force
But it could be a cool tutorial to teach you, a practise mission taking out a rebel installation or something
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