Complex sentence: The rules are based on the "knockdown karate" rules explained above, but modified to use boxing gloves and allow punches to the face, although it may be argued that it is unclear where this karate competition format ends and kickboxing begins.
Split into simpler sentences: The rules are based on the "knockdown karate" rules explained above, but modified to use boxing gloves and allow punches to the face. Although it may be argued that it is unclear where this karate competition format ends and kickboxing begins.