Dammit, now metalslug is gonna use the cheap way out. Lame.
I don't know how you're having so much trouble, he only shoots you with anesthetic bullets, so even if you get hit, just heal yourself, try to track where the shot came from, retaliate, then rest up to gain stamina back and find him again.
He does like to appear right up in your face, I remember I walked over him without even realizing it and he popped up, tried to whack me or something and then ran away, and I finished him off with a sniper round to the back while he was trying to escape. I was pretty satisfied.
--
~Halo You're not the brightest.
http://img404.imageshack.us/img404/907/bandfinisher.jpg