I just started playing this game and I'm already stuck. I went through the first level, the cellar... I have 1 rat left to kill but I can't find it. I don't have the key to the sewer or whatever that locked door is supposed to lead to. I knocked down the wallnear the locked door and found some junk in a treasure chest. I've smashed all the barrels and killed all the baddies....where's the last stupid rat????? And where am I supposed to find the key to the locked door???

The last rat is somewhere before you started seeing the kobolds. You just missed it by accident. The bartender will give you the key to the sewers once you kill the last rat.

Tod