I played the game a bit last week. It runs really inconsistently in DosBox, lots of slow-downs. The gameplay speed seems to be dependent on CPU speed you set.
I picked Jean-Paul and Thorn, and made it through the first maybe 8 fights by mostly just button mashing. Then I kept getting killed. After that I found the low sweeping kick (down, back, kick) had a long reach, as well as one of the other kicks (back, back, kick) – mostly unstoppable.
I was playing on easy mode – which also meant I couldn’t fight the boss. He tells you to go away!
I remember we had this game on the family 486 when I was a kid. I think it was only a shareware version with limited gameplay. Was good fun to revisit. I think I’ll play some more on a harder mode, learn some of the moves and try the career mode others have mentioned.