Rindo-Kan Karate is a fictional martial art style used by Makoto and Skullomania. There is also a dojo that teaches it, though not many people know of it. Because of this, Makoto fights to show the world how strong the style is.
Rindo-kan Karate bears a resemblance to (and is most likely inspired by) the real-life art of Shoto-Kan Karate, much more so than the Ansatsuken fighting style that Ryu, Ken and the other "shoto" fighters use.
Rindo-Kan Karate is boisterous and aggressive style characterized by powerful punches and kicks, as well as formidable karate techniques such as chops and throws.
The overall style revolves around sudden strikes with precision, often anticipating an opening to deal heavy damage to the opponent.