Sphere

"Get Blue Spheres."

- Opening line of Special Stages.

Spheres (スフィア) are collectible, floating or non-float y items, which by most of the time can be found at Special Stages. There are different colored and numerous variations of Spheres, that in each game gain different purpose for the player, who ever touches them. Spheres have made first appearance in Sonic the Hedgehog 3.

Sonic the Hedgehog 3 & Knuckles
First appearing in Sonic the Hedgehog 3 and its add-on continuation Sonic & Knuckles, the game introduces to three different type of Spheres, that are featured in the game's Special Stages: blue, red and yellow. The blue ones are collectible, which will transform to the red sphere after running past through. The player has to avoid red spheres, as they can transport out of Special Stage to the regular zone. Yellow spheres can only be found at Sonic & Knuckles, as the player is runs toward it, he/she flies to the air and lands after flying over six rows of spheres.

The goal of Special Stages is stated at the beginning of the level: the player has to collect all blue Spheres from the arena in order to complete it and get reward with one of seven Chaos Emeralds, while the player has to avoid all red spheres at all cost, which can turn out of them once the player has run past blue spheres. The player is also able to avoid red spheres by Spin Jumping over them. The counter at the upper left corner tells to the player how much blue spheres are left. There are numerous red sphere groups at the Special Stages, as the player has to follow the routes and find blue ones, that can be found mostly on nine groups or even more. If the player run past blue spheres on the borders of group, all of spheres on the group turns out number of rings, that the player can collect to get continue and the Ring Bonus from the Special Stage. This technique doesn't work on small group of blue spheres, that have less than 4 blue spheres. Once all blue spheres are collected, all objects on the Special Stage rise up and the player has got Chaos Emerald.

Knuckles' Chaotix
Blue spheres make appearance in Knuckles' Chaotix, where they are also featured in Special Stages. Like in previous appearance, the player has required to collect certain amount of Blue Spheres from the Special Stage before the player has pass the each check point. They are singly laying around the route of Special Stage and can be found on ceilings and other tricky places. When the player collect the blue sphere, he/she got the sphere without its turning to the red sphere. If the player hasn't got enough of Blue Spheres after passing the check point, the player has to repeat the section to get amount of Blue Spheres before the ring count goes to zero (which functions as a second timer in the Special Stage). If the player collects all Blue Spheres after two check points, the player has got one of Chaos Rings.

Sonic Heroes
Multiple, different looking Spheres made appearance in Sonic Heroes, where once again the player can find them from the game's Special Stage, which come this time on two variations: Bonus Challenges and Emerald Challenges. Here, there are three different kinds of Sphere types, that have mostly the same purpose to gain more power for Power Dash, which has its own three sectioned meter. The first ones are Multicolored Spheres, that different colored Spheres on two or four groups on long strings. These Spheres will gain small amount of power to the Power Dash Meter. The slightly larger blue spheres with star prints called Super Spheres (スーパースフィア) will gain more power, that is worth of ten normal Multicolored Sphares. The red spheres with the star prints called Score Spheres (スコアスフィア) can apparently double the dash power 10 times of Multicolored Spheres.

These two last mentioned variants can be also found floating in the middle of the route, which are able to collect by bouncing on springs or hang on pulley and control it to the left and right while collecting spheres. Some of these are set on pillar formats, which can be collected by using Fly-type character. Some point of Bonus Challenges, neutral Chao and Dark Chao on the large balloon appear and both of them starts throwing extra amount of sphares or bombs. Normally if the player keeps running past the numerous sphere strings, it will gain huge amount of points and extra time for the player. This can come handy in Emerald Challenges, where the player has to catch Chaos Emerald by staying closely on these strings as possible.

Sonic Generations
Spheres make yet another appearance Nintendo 3DS version of Sonic Generations, as they repeat their exact role in the game's Special Stages, which are based on ones from Sonic Heroes. All three types of spheres multicolored, Super Spheres and Score Spheres make appearance with same fuctions as well, as they can increase the player's boost guage.

Trivia

 * Originally in Sonic the Hedgehog 3, the Japanese instruction manual stated these items as Ball (ボール). In later games since Knuckles' Chaotix, the Japanese instruction manual have titled them normally as Spheres.
 * Despite being collectible orb-shaped objects, spheres are not to be confused with Gumballs from Bonus Stages in Sonic the Hedgehog 3 and Sonic & Knuckles. As Gumballs earn items, that are inside of them, Spheres only earn power for boosting or points.
 * Some objects and obstacles like Bumpers or Bombs are seen to have similar shaping as Spheres.