Sonic & Knuckles + Sonic the Hedgehog

When Sonic 3 is locked-on to the original Sonic the Hedgehog or Sonic Compilation via Lock-On Technology, the result is a deceptive "No Way!" screen. However, by pressing the A, B and C buttons together players can access Special Stage levels, commonly known as the "Blue Sphere" levels. Levels can be accessed by inputting a twelve digit code, every number combination a different variation of a Special Stage level.