Sometimes, we may stumble across them by pure chance, or after pulling off some ridiculous requirements. Regardless, secret levels in video games are usually a real treat, since they tend to allow the developers to go all-out with their ridiculous ideas. You’d be lucky to find another game that lets you swim through a giant toilet to kill aliens, or sneak past guards with no clothes on. If that sounds weird enough, then prepare yourself and read on…
 
Fun Park | Command & Conquer
Command & Conquer was a game that put the real-time strategy genre on the map, though it was none too easy. The same can be said about its nightmarishly difficult add-on The Covert Operations. What the packaging doesn’t tell you, though, is that it also contains a mini-campaign called “Fun Park”. Your enemy consists of dinosaurs. Most of them are pretty slow, but they can take a lot of damage. In the final mission, you can even command an army of the prehistoric creatures, too.
Obviously, this is a parody of the hit-novel “Billy and the Cloneasaurus” by Seymour Skinner, which in turn was shamelessly plagiarized by Michael Crichton.

 
The Ratacombs | DUSK
It’s safe to say that DUSK may be one of the best throwback FPS titles to date. Its quick-paced combat, unsettling atmosphere and slick controls have earned it Overwhelmingly Positive reviews on both Steam and GOG. But if there’s one thing that players really hated, it was the rats. These ugly little freaks seem to do massive amounts of damage. So, what did David Szymanski decide to do for the game’s third episode? Make a level filled with them, of course!
The Ratacombs is actually inspired by a level from Planescape: Torment, albeit mirrored. There’s 137 rats in it, not to mention a giant one named One as Many,

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