To defeat this Boss, play as Sonic. He has three lives. To catch him, get a good head start. He is very quick. Do not make a mistake or it will take awhile to catch up. When you start, you must catch up to him using the turbulence streams and the grind rails. It helps to make quick work of him. Also, use the ramps and try to perform as many tricks as possible, but do not take any unnecessary risks. When you start getting close to him, use your boost to go through the lamp-like object below him, and he will let out a cry. Then the stage will look like a digital place for a period of time. After it returns to normal, repeat the process. Once you deliver the third strike, it will quickly turn into a race. If you are near the finish line, use the turbulence and your boosts at any costs. When you win you will see an intermission sequence showing what the legendary treasure really is.