Civil Protection/YMMV

"Dave: What do the Combine look like anyway?
 * High Octane Nightmare Fuel - The Halloween Safety episode. Though the ending could be considered more of a parody.
 * The Tunnel. Ross Scott deliberately stated he wanted to do a scary episode. He succeeded.
 * Magnificent Bastard: Mike has this opinion about the Combine.

Mike: You know, I'm not sure either. That's how good they are. It's not like they showed up themselves to conquer the earth. Oh no, they were kicking it back at their homeworld, sipping alien martinis, while they sent another alien race, they had already conquered, to come conquer us, for them! Now that's just slick.

Dave: Wow. And now we're working for them.

Mike: Yeah. It's the pyramid scheme from hell."