Blue Sphere

Blue Sphere is the game created by locking on Sonic and Knuckles to Sonic the Hedgehog. It is a compilation of 128,016,000 "Special Stages" in the same style (and engine) of the ones featured in Sonic the Hedgehog 3 and Sonic and Knuckles. After completing all 134,217,728 (2²⁷) stages, it repeats from the beginning.

Each time you complete a stage, you are given the password for the stage. Also, each stage has a difficulty level assigned to it, represented by an icon. There are 13 difficulty levels in all. Difficulty is assigned based on the number of spheres in each region of the stage's map, so some level 13 stages might actually be less difficult than level 12 or 11.

List of icons by difficulty level (Note: Each difficulty level contains the icon of all difficulty levels below it)

1. Nothing
2. Sonic
3. Tails
4. Knuckles
5. Robotnik
6. Mecha Sonic
7. Masked Robotnik (flying)
8. Chickens
9. Squirrels
10. Rabbits
11. Master Emerald
12. Sonic & Knuckles logo
13. Sonic turns into Super Sonic

Blue Sphere can also be created by locking on Sonic and Knuckles to any other Sega Mega Drive/Genesis game, producing one of the stages featured in the Sonic the Hedgehog Blue Sphere, based on something in the header of the game.

Please note, however, that playing these levels via a game with battery back up will erase saved games. Also note that this won't work with games made after Sonic and Knuckles was released. There are also some instances of it not working with games made before Sonic and Knuckles, such as Phantasy Star IV.

The name Blue Sphere comes from the name shown in its listing in Sonic Mega Collection.

External Links

• Blue Sphere generator