Atomic Robo-Kid

Atomic Robo-Kid is a horizontally scrolling shooter released by UPL in arcades. The player controls the titular character through six levels of increasing difficulty and must face an alien "Governor" boss at the end of each level (which are so large that they count as levels in their own right, as some of the bosses take up multiple screens), followed by a "duel" level against other Robo-Kid-sized robots. Many levels branch off into others, so the player has a choice of which zone to enter next, adding to the replay value.