Spider Mastermind - A giant robotic weapon resembling a spider with a giant brain (which has a face on it, and even little arms as well) acting as the main unit controlling it. This monstrosity has a powerful machine gun attached to it, and if you stand anywhere where it can see you, you'll find your health quickly dropping unless you find somewhere to hide. The Spiderdemon is the boss at the end of Episode 3: Inferno.