I want to do "Eclipse Scythe Master" achievement on ninja gaiden 2, but....?

I just beat the game on warrior, and actually it was a bit easy for me. I want to do the Eclipse Scythe Master achievement. How do you get the Eclipse Scythe Master achievement if you start out with the dragon sword? Does this mean i have to kill all the enemies up to and including Volf with projectiles and ninpo? How do you possibly do this???