Originating from the world of Mobius, they are seven legendary and mystical stones with powerful properties and abilities that gives one the power to rule the world. Those that hold the Emeralds can use their powers for a variety of things, such as achieving a super form, powering machines and warping time and space. Anyone who possesses all seven of the Emeralds can command near-unsurpassed power.
The Emeralds have been the center of countless world-threatening conflicts across space and time, and have been targeted by multiple factions on both Earth and beyond, who seek them for their immeasurable powers. In the hands of villains they have been used for doomsday weapons and schemes for world domination and in the hands of heroes, they have been used for good. Over time, the Emeralds have been gathered multiple times, though after each usage they scatter themselves and reset the hunt for them.
Described as a legendary stone that give its possessor the power to rule the world, each Chaos Emerald is said to possess mystical properties and contains unlimited amounts of highly potent and powerful chaos energy. The power of one Emerald alone is unmatched by pretty much anything else in the universe, except by the Master Emerald. Each Emerald emits highly concentrated energy in the form of electromagnetic waves which can disrupt machinery.
The main power of each Chaos Emerald is described as being able to transform thoughts into power; by "sensing" people's thoughts, the Emeralds are able to generate the chaos energy they contain which make the Emeralds' an everlasting source of pure energy. As an offset of this power, the Emeralds can even bend reality to achieve certain feats, such as showing visions. Additionally, each Emerald can float in midair on its own power, and can orbit around the one who uses it.
The Chaos Emeralds' power can be harnessed with or without physical contact and over great distances. When harnessed by living beings, the user can perform different techniques, such as Chaos Control, and occasionally get their own abilities enhanced. Even just two Emeralds can provide a user with overwhelming power. Harnessing the power of all seven Chaos Emeralds will transform one into a Super Form, a form that grants flight, invulnerability, chaos energy-based powers and potentially infinite strength and speed. However, these transformations do not last long, as they consume tremendous amounts of energy. The Emeralds can also be harnessed to power and/or empower machinery, such as the Eclipse Cannon.
The type of chaos energy the Emeralds produce is based on thoughts/emotions. Positive thoughts, such as friendship and caring, generate positive energies that comforts who holds them and negative thoughts, such as anger and hatred, generate negative energies that further increases the user's rage. If the Emeralds are either absent of the negative energies (or possibly positive energies) or all of their energy, they will become inert and apparently powerless. The only known ways to restore the Emeralds from this state is through peoples' thoughts or the Planet Eggs.
Chaos Emeralds have a tendency to react to each other. Whenever at least two Emeralds are brought together without being given time to adapt to each other's presence, they either fluctuate or will release immense quantities of energy. Additionally, all seven Emeralds being in one place results in them releasing energy, sometimes on such a level that they trigger Chaos Control, that pushes them away from each other, meaning that all seven Emeralds can only be used for one purpose together before they scatter again.