What if the music loops and changes in the special levels? Like, in the Inferno module, there is a special level called Ptlomea or something that starts out with you being presented a tunnel with a BFG, 4 large medpacks, and red armor w/ plasteel boots at the end. You can go out to the rewards (also includes plasma) and get them, but there are no monsters. (EVERYONE knows that if you you see an unguarded BFG just lying around, SOMETHING is VERY wrong). So, once you try to reenter the tunnel, it gets sealed off and all these monsters pop out of NOWHERE and rape you. What if you had an eerie, subtle music track in the beginning, and once the walls close off, it becomes a bunch of hardcore guitar riffs? Could you start playing a separate track in a level?