This boss was memorable because it was the first important role that Metal Sonic played in Sonic CD, the game in which Metal Sonic debuted in the series. As the name suggests, you don't actually fight Metal Sonic; you must beat him in a race in order to rescue Amy Rose (some victory prize she is). This boss wasn't terribly difficult, but it is somewhat cheap because you cannot attack Metal Sonic, yet he can attack you. Metal Sonic also uses a speed boost to plow through the track's spike traps, while Dr. Robotnik follows the race with a laser beam that instantly kills you if you touch it.

 

 

 

 

 

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