I suspect many others shared my appreciation of fighting films while growing up in the 80's, with classics like Bloodsport and Best of the Best to watch repeatedly, but I guess I kind of grew out of them. Not so long ago though, I happened upon a YouTube clip of some guy performing all sorts of crazy flippy spinny jumps and kicks on various hapless opponents. I soon identified him and the film in question and had to watch it. It turned out it was part of a series though, so I figured I might as well watch all of them and report back here with my largely inconsequential verdict!
Undisputed II: Last Man Standing (2006)
Undisputed III: Redemption (2010)
Boyka: Undisputed (2016)