After all the Chaos Emeralds in the universe were sent to the Zone of Silence during the Great Harmony, Feist merged all of them into seven different colored gemstones and used their power to reshape the Zone of Silence into the Special Zone. In order to make sure the emeralds did not fall into unworthy hands, Feist created challenges so that only those who succeeded could gain an emerald, which served not only to keep the emeralds safe, but to entertain him as well. So far, his challenges have proved so difficult that not even the most formidable and resourceful of G.U.N.'s agents have been able to complete them, and thus, no one has obtained an emerald through a challenge, but emeralds have been obtained through other means. (StH: #169, #170 SU: #4)
- Obstacle Course: The obstacle course is a course of fire, steel, and cloud where the challenger has to run down a small wooden bridge while making sure not to fall into the boiling lava below, and avoid hitting the spiked balls surrounding it and going through a loop.
- Cuboid Maze: The cuboid maze is a floating and rotating maze in the shape of a cube with three entrances. The person taking the challenge must make it through the maze to the center with a floor of spikes within sixty seconds, but even if the challenger reaches the center in time, Feist will cover the Chaos Emerald there within gemstones and the challenger must then destroy them in time to receive the emerald.
- Race: A curved tube pathway littered with mines. The objective is to simply reach the Chaos Emerald at its end.
- All the challenges Feist makes are based on Special Stages from early Sonic the Hedgehog games, such as the obstacle course which is from Sonic 3D, and the maze which is based on the first ever Special Stage from 1991's Sonic the Hedgehog.
- There have been 2 "exceptions", to Feist's rules:
- Sonic and Tails were able to receive an emerald from Feist as "thanks" for sending them to him in the first place, thus making them a one-time "exception" to the challenge rule. (StH: #170)
- When Team Dark came to receive a Chaos Emerald for G.U.N, they failed all the challenges, so Rouge let Omega use "Plan B", in which Omega unleashed his arsenal against Feist while Shadow and Rouge grabbed the Chaos Emerald he was holding. Feist became angry, but Shadow used Chaos Control to escape before Feist could attack them. (SU: #4)
- The Half-Pipe from Sonic the Hedgehog 2 was also seen in the background but no one took part so far.