The outer wall is protected by three parapets - the west parapet holds Sisters Theodosia, Lucretia, and Ursula. The center parapet holds Sisters Jade and Isolde; the east parapet holds Brothers Anthony, Boris, and Nathan. It's worth noting that these three groups are locked into their parapets by locked doors. In the hallway between the main hall and museum area, Brother David can be found - any of these groups can be deadly to characters in medium armor, and some or all may take pot-shots at you from the walls as you approach. Thus, you may want to consider your entry strategy carefully.