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The game has 4 different endings:

1. If you fail to save the general/chief, you play an alternate Round 7 (The City Hall/The White House). At the end of this, you have to face a stronger Shiva as the last boss, instead of Robot Y (known as Neo X in Bare Knuckle 3).
2. If you do rescue the general/chief, you play the real Round 7 (The Robot Facility). You are expected to defeat Robot Y within a time limit. If you beat it after the timer expires, the bombs will still detonate in the city, turning it into a complete ruin.
3. If you destroy Robot Y before the timer expires, the bombs are defused and the city is saved; this is the best (and true) ending of the game.
4. There is an "Easy mode" ending in the U.S./Euro versions where Robot X in Stage 5 is the last boss. After defeating him, you are told to play the next difficulty mode.