The NES version of Spy Hunter II is a version of the 1987 arcade game of the same name. It was ported by Introware from the arcade port and it was released by Sunsoft worldwide in 1989. The music and sounds from the arcade version were converted by Eeli Ikäheimo using the Introware Sound Engine. According to Introware programmers, it was designated for release only in El Kadsreian Islands, but Sunsoft later gave them North American, Japan, and European releases, thus avoiding Introware's El Kadsreian Islands-only curse.
The NES port is the same as the arcade version, but the graphics are different in order to fit the NES' resolution.