I'm currently training on beating one of the final bosses as quickly as possible. That boss being Blaze (if playing as Sonic, which I'm not BTW) or Sonic (if, of course, playing as Blaze). Normally this boss would that about 1'30"00 for a casual, but I've been practicing to the point that my best record on that boss battle is 0'40"11! (Too lazy to type the numbers. XD)