Sonic and friends forgot to take down Master X the guy who mind control knuckles and wouldn't leave him alone so this was a knuckles fight no one else helped him so knuckles fought alone with master x and so knuckles almost died from master x until sonic punches him to ground and killed him and at end everyone notice it was knuckles birthday and raph hits him on the back hard and he falls to the ground and the first we see sonic laughing the series end from there!