I have been over level 4 a few times and can't find the area where the boss with the key is. I played some time ago and if I remember correctly it is near one of the large sections of wall. My starting attempt to find it after exiting the lift and taking a couple steps I turned left and went to the wall with no openning. There was a left side door and a right side door. I tried the left one. I went all over in that direction and could not find it. The next try I went right and could not find it there. I was even using the bright stone and could not see where to go. I did see the large areas of stone but no entrance for the boss. What number square is he on? That and any other help would be appreciated. Thank you.