Every successful run after the first unlocks a set of themed characters, such as the entire Captain Commando Boss Rush Mode:

: The same method used in Arcade Mode (breaking barrels and hitting signs) works for the initial secret set. For another hidden fighter, select Moria and, at the start of the Cadillacs and Dinosaurs stage, double jump and attack backward without moving forward first.

: Certain versions (like v4.0) have unique hidden fighters (e.g., Moriah, Batsu, Eliza Masters) that may require specific inputs or searching hidden areas, like kicking signs in the "Slums" area. Instant Unlock via Save File

For players who want the full roster immediately, the most effective "workaround" is downloading a completed save file:

Stop grinding. Stop believing fake combo codes. The working method to unlock all characters in Final Fight LNS Ultimate is through . The game is a masterpiece of fan development, but its unlock system is overly archaic. There’s no shame in bypassing it to enjoy the full, incredible roster.

And the seventh.

: Community members on sites like Speedrun.com have uploaded "All Unlocks" save files that you can place in your game folder to immediately access everyone.