Hints Level 4
There are movable walls at beginning of the level. After pushing to the other side, push your way back to the stairs to find a Dwarf key. Now return, and turn right. Somewhere along this corridor is a chain switch. Pull on it.
Various Glitches
Enemies can never open a door or go up or down stairs. You can see items behind a door when you enter the camp screen. A spell, arrow, or dart flying at you will be blocked if you close a door between yourself and the projectile. Cursed items can be removed without a remove curse. Sometimes you will know what an item is without casting Identify.
A Mind Flayer's (Illithid's) paralyze spell can be removed instantly by entering camp screen and choosing "Rest Party". The message "Monsters Near" will appear, but everyone's Paralyzation status will be gone. Note: This only works if you are already fully rested (everyone has all spells and you are full HP), and you have to turn so that the Illithid is not in view.