Satan Spawn? It's actually kinda funny - My brother and I were huge fans of Doom when it first came out on the PC. And for long after, even. If you aren't familiar, there's a huge floating one-eyed thing in the game called a cacodemon. He told me he was on the way home from work, flipped the sattelite radio to the metal channel or something and this song just happened to come on. He called me immediately. The reference made him think of Doom, but the song had him laughing pretty much the entire time. I am not capable of taking the song seriously at all, it's more an amusement factor. Impressiive musicianship though, despite not being able to understand any of it.
On the other hand, "Rockin' the Beer Gut" is about a guy walking into a bar and being attracted to a chick with a beer gut. It's one of the most pathetically godawful things I have ever been made to listen to. Not to mention entirely unrealistic.