Enable the "Level select" and "Debug mode" codes, then go to Emerald Hill Zone Act 1 or 2. Transform into the default ring and press SQUARE(4) to become an invisible object. You will be a waterfall. Place waterfalls by repeatedly pressing A from where you start to over by the "coconuts" enemy in the tree . Eventually you will see the life counter in the corner change to Ashura's. Turn Sonic into himself again and he should come out as Ashura, a green and black version of Sonic. You can change his color by continuing to place waterfalls. Watch the life monitor to see the changes in color.