Kid Niki: Radical Ninja, known in Japan as Kaiketsu Yanchamaru, is a 1986 platform video game developed and published by Irem for arcades. Initially released only in Japan, it was later released internationally by Data East in 1987 for the Nintendo Entertainment System. The arcade game runs on Irem-62 Hardware, the same as Kung Fu Master.
The differences between 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.