Id have to go with "Ninj-HA!", with a full body black outfit and full head mask with only eye slits, fingerless gloves over heavy duty grip gloves, climbing shoes and a wooden kendo sword, since i wouldn't want to actually spill any blood hitting someone. Id be able to scale walls up to a height of about 7ft with the grip on my shoes/gloves, then hope the silhouette of me holding a sword shaped object scared criminals off - since if it didn't id be forced to clamber down the wall again then wave my wooden stick around irratically trying to hit them since I have neither any climbing or actual sword fighting skills.