Play as Sonic in Story or Trial mode. Select the Silver Boss battle. Get as many rings as possible (fifteen). Then, go to the alley in the corner. Try to get as far into the corner as possible. When Silver uses his levitation technique, try to get back in the corner. Silver will try to use the levitation technique again. The rings will be behind you. You should be able to collect the rings before hitting the wall and dieting. Then when you hit the wall, try to collect your rings. You will then go outside the level's boundary. You will be able to walk on invisible bridges and hit other invisible things. Silver might even also get out of the level boundary and throw you out of Soleona and you will keep flying forever.