Kid Niki: Radical Ninja, known in Japan as Kaiketsu Yanchamaru (快傑ヤンチャ丸, lit. “The Wonderful Yanchamaru”), is an arcade game developed and published by Irem in 1986, and was later published outside Japan by Data East in 1987. The arcade game runs on Irem-62 Hardware, the same as Kung Fu Master.
The differences between the Kid Niki: Radical Ninja and Kaiketsu Yancha Maru are minimal. Aside from text translation, the most glaring difference is the main character’s hair style. Kid Niki’s hair is more “punk rock” with wild spikes and a ponytail in the back. Yancha Maru’s hair has more subdued spikes and a topknot (or chonmage). In the arcade version of the game, the main character’s keikogi is yellow while it is red in the home ports.