In Renegade, the player controls a vigilante named Mr. K, who fights a variety of street gangs on his way to save his girlfriend. Unlike other similar games like Double Dragon and Final Fight, the playfield is limited to one two-screen-wide area (a subway platform, a park, an alley, a parking lot) and does not scroll continuously. Out of the four levels in the game, the first and third each begin with the player fighting a group made up of two different types of enemies; one with a stronger attack but less hit points, and one with a weaker attack, but the ability to hold the player and more hit points.
When only three of these enemies remain (in any combination of the two) their boss will come in from the sidelines and join the fight. When the boss is defeated, all remaining enemies retreat off the bottom of the screen, and the stage ends. The second stage follows this same formula, but begins with motorcycles trying to run the player down, and brings in the normal enemies once the motorcycles have been defeated. The fourth level replaces the two normal types of enemies with a single type of knife-wielding enemy who can kill the player in one hit.
The game has an unusual amount of voice sampling for the time it came out; the "credit" sound is a voice saying "Good luck, kid", and each boss has a different taunt, including "Get lost, punk!", "Beat it, scum!" and "Give it up, boy!".
Each level of Nekketsu Kouha begins with a short cutscene of your friend getting beaten senseless by the next level's thugs until you chase them off, which is completely absent from Renegade. The enemies' sprites have also all been changed to look more westernized; the first level's schoolboys and bald schoolboys in school uniforms have been changed to 80's-style thugs and black men in hawaiian shirts respectively, the second level's bousouzoku have been changed to long-haired, musclebound American bikers, etc.
Naturally, all the voice samples in Nekketsu Kouha are in Japanese, although they say basically the same things as in Renegade. Nekketsu Kouha's western localization takes heavy influence from the film 'The Warriors'. (Wikipedia)