Collect all the rings and finish Level 1.
Collect all the rings and finish Level 11.
Collect all the rings and finish Level 21.
Collect all the rings and finish Level 31.
Collect all the rings and finish Level 1000.
Collect all the rings and finish Level 100.
Collect all the rings and finish Level 10.000.
Collect all the rings and finish Level 30.000.
Collect all the rings and finish Level 9089.
Collect all the rings and finish Level 54479233.
Collect all the rings and finish Level 113407233.
Get through the first 7 levels with perfects in all of them (use the passwords to go back after getting a perfect).
Get through level 8 to level 14 with perfects in all of them (use the passwords to go back after getting a perfect).
Collect all the rings and finish Level 81193028.
Collect all the rings and finish Level 23411487.
Collect all the rings and finish the special stage you get by attaching Sonic Spinball.
Collect all the rings and finish Level 123456804.
Collect all the rings and finish Level 2013.
Collect all the rings and finish Level 69.
Collect all the rings and finish Level 420.
Collect all the rings and finish Level 123456789.
Collect all the rings and finish Level 666.
Collect all the rings and finish Level 88166662. Good luck >;).