I had a Sega Master System as a kid and played a lot of a game called Black Belt where you have to kick and punch many bandits in the face to rescue your girl (pretty standard story at the time). I still think it's one of the best games on the console. Many years later I've found out that the original Japanese version of the game was a 北斗の拳 (Hokuto no Ken) game. I was trying to play the Japanese version but there was a mid-level mini-boss I couldn't figure out how to beat, so I looked for a walkthrough online. Found this one: セガ・マークⅢ『北斗の拳』 - 北斗が如く 攻略 (dswiipspwikips3.jp) It's actually a 攻略 inside a 攻略. The site is a guide to the 北斗が如く game for the PS4 (using the same engine as Yakuza, 龍が如く). Inside the game there's a point where you can find a Sega Mark III (the first Japanese version of the Master System) and you can play the original 北斗の拳 game on it.