I there a point to all this?
I was trying to figure out the game and got a message that some corporation "frowns on camping." That's how you deal with camping? Threaten to blow me up? Left 4 Dead did it with Smokers, teaching us the burden of curtailing behavior like that is your job as the designer, not mine. Not that it mattered, the level is smaller than my backyard and never changes. Who is this guy following me? Why am I fighting aliens forever? Halo has already been made, if you're going to make yet another incessant boom-fest, you have to put some imagination into it, loud noises and guns guns guns have been done to death. I recall this is a sequel?
You want to shoot aliens? Play X-Com. Not the new one. The 1994 game people are still playing. That's how you shoot aliens.