Sonic Generations

Perfect Chaos was a boss from Sonic Adventure. This boss requires you to manage your rings well (just a little) so that you can just boost when it's needed. At the start of the boss fight follow the path towards Perfect Chaos and pick up as many rings as you can, once you start to get closer to him start holding to boost towards him and Sonic will boost right into him and damage him. The second time you follow another path that lead you up springs, at the right timing you have to hit when the green lock on symbol appears, after this hit you'll have to hit him one more time similar to the first attack. After the 3 hits you'll be on pieces of rubble, follow it towards Perfect Chaos and finish him off.