Chaos Emeralds are powerful artefacts that exist in almost all Sonic games and media - they are capable of transforming a character into a super-being akin to a demigod when collected and are depicted as several brightly colored gemstones: there is also a related artefact known as the Master Emerald which contains even greater power than the Chaos Emeralds and is said to be the source of the Chaos emeralds.