I've played through the entire game myself and I gotta say it's a product of its time. You go around killing aliens throughout various locations such as Los Angeles, the moon, Shrapnel City (from the first game), and various parodies of other iconic locations and cities around the world.
Some levels feature nightclubs, red light districts, adult movie theaters, adult movie production studios, etc. There was even an exclusive level for people who subscribed to Penthouse Magazine.
Other than exotic dancers, models, and adult movie actresses, you'll encounter women who are stripped naked, covered in tentacle vines or cocoons surrounded by eggs that hatch into little booger parasites. The aliens' goal is to make human women incubators for an enemy you'll encounter in Episode Four: The Birth.
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I am sick, and in so being I am the healthy one.
If my darkness or eccentricity offends you, I don't really care.
I will not apologize for being me.
There is no such thing as perfect. We are beautiful as we are. With all our imperfections, we can do anything.