Conner refers to this character as a 'specter'. This enemy is known as a Skelhamr in the debug mode, most likely because it guards the Hammer. It doesn't wield a hammer however. It shares this file name with a skeleton commander found in the Realm of the Sun. Interestingly, this skeleton was originally intended to have its own graphic, and appear egyptian like. The graphics still exist in the files, and the programmer notes can be found in the 2000.msg file. The programmer notes refer to it as the 'hammer skeleton'.