The easiest way to get through the Demon Door by Hobbe Cave is to get your combat multiplier high by beating up a villager. All you have to do is go into Bowerstone South, and get any random woman to follow you. Then you must take her to Bowerstone Quay and start beating the crap out of her, until you think your combat multiplier is high enough. This does get boring after a while, but hang in there. And if you want to make the job easier for you, give the person three beers so they don't scream for the guards or run away. Then all you have to do is teleport to the door, and have it swing open for you.
And if anyone out there, who is married to Lady Grey, wants to be completely evil for some reason, just do the same to her.