Double-or-quadruple-the-number-of-sprites-to-avoid-it-looking-like-ass difficult.
Which is to say, not hard at all? Why redraw the sprites when the computer can?
http://www.students.uwf.edu/aen3/mauler.zip
That was like...2 minutes of work. A minute-and-a-half was spent looking for the "rotate-sprite-and-avoid-looking-like-ass" program.