All Alone

This is a single player WAD for Doom II, but has DM start points if you want try. A single person called upon to make his/her way through terror filled rooms and hallways. You first arrive when your transmat beam goes awry, and you find yourself on a large dias. You take stock of your surroundings and see several nasty Demons, thank God they are barred up in a room ! You see what appears to be a lighted red skull in a barred window far above you. You also see two locked doors, one obviously needing some kind of pass-key. But wait .... there is a switch in the room with the Demons. You then spot a wicked, blood encrusted chainsaw near the room, but even with that you might still not kill all those creatures. Looking around carefully, you notice piles of dead players near embossed carvings of a hideous creatures near the door requiring a key. As you wonder about the carvings, you notice scratch marks around them ....hmmmmm could they be switches ? could they somehow help me escape the Demons and get the hell out of here ? ............ This is only the beginning of a dangerous road to freedom.

Lmp included will give away some secrets and the trick at the beginning.