When I first saw the achievement list of Ninja Gaiden 2, I thought there was no way I could ever get a 100-hit combo. I watched my boyfriend do it real easy just now.
In Chapter 6, you’ll come across a large area with mounds and mounds of bones for your quick little ninja feet to run on. A dozen skeletal creatures will appear and will chase you around. Run away from them and jump, while throwing your Shuriken at them. Make sure your hit counter remains on the screen and that you never get hit. You’ll only need to throw them about 25 times before you get the achievement.