I always thought of a new playable mod. Such as a playable rogue Battledrone. Which has a lesser rof for the lazer, but has a lot more health which could have something to do with that it is an older kind of battledrone that was put out of use for the newer types of battledrones. Then in this story it could have this rogue battledrone wiping out Marine bases and sectors throughout a different part of the Notrium world to free the long forgotten battledrones. Or we could scratch all this and have it set like in Opposing Force where the Marines were first colonizing the planet and had to wipe out the aliens for colonization. But this could have a longer story to it and would be played with the Marines.