Sonic & Knuckles/Special stages

In the combined version, Sonic 3 & Knuckles, these are accessed by entering the Hidden Palace Zone through the Special Rings. As Emeralds are acquired, they light up at the altar. Once the collection of the Super Emeralds has begun, the ordinary Chaos Emeralds can no longer be used to become Super Sonic or Super Knuckles. After all 14 Emeralds have been collected, Hyper Knuckles, Hyper Sonic, and Super Tails become available.

Stage Maps
the goal of these Special Stages is to collect a certain number of Blue Spheres. There are also rings in the levels, and if 50 are collected, a continue is awarded, and when all rings in a level are collected, a PERFECT is announced and the player is awarded 50,000 points. After a blue sphere is collected, it turns into a Red Sphere, and there are also Red Spheres that pre-exist in the level. If a Red Sphere is hit, the stage ends. However, if a player passes entirely along the outer perimeter of a field of blue spheres and turns them all red, then the entire field of Blue Spheres inside will be transformed into rings, and all spheres will be instantaneously collected. This technique must be used to achieve a perfect.
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