There is a glitch in the NES version that can cause an "invisible man" to appear in Mission 2. Abusing this glitch can allow the player to obtain full hearts, as it's possible to beat the "invisible man" as much as the player desires without getting hit back.
Contributed by Mass Distraction
Near the end of the first mission in the NES version is a missing ladder that the player can still climb. Climbing to the top of the ladder only makes the player appear back at the bottom, and if they are holding a weapon while climbing it, the weapon will get stuck in the wall if the player is struck by an enemy.
Contributed by Mass Distraction
The game was originally planned to be a sequel to Renegade (Nekketsu Kōha Kunio-kun in Japan). The game was given a new art style and a new story to appeal to a more international audience instead of the Japanese one that Kunio-kun was known for.
Contributed by gamemaster1991