The Chaos Crystal is a relic hailing from the Sphere of the Gods, able to augment and intensify small amounts of energy, turning them into incredibly large bursts of raw power.
Another facet of the crystal is that it is a wish granter, giving whomever it's surface reflects whatever they're hearts desire if provided enough energy. In the possession of the Earth 2 United States Government, they used the crystal to create a planet busting weapon powered by it in an attempt to incapacitate the Superman of their world if he ever went rogue. The Batman also used a fragment of it to turn the radiation of a small piece of on hand Kryptonite into a much larger burst of radiation capable of incapacitating Kal-El of Prime Earth. However, the Superman of Earth 2 destroys the crystal and scatters many fragments of it in different directions.
Years later, it is revealed that Ra's al Ghul hid a fragment of the crystal inside the sarcophagus of Damian Wayne. Glorious Godfrey confronts Batman, Ra's, and their allies in an attempt to retrieve the crystal. Even with the intervention of the Justice League, Godfrey succeeds in taking Damian's coffin back to Apokolips along with the crystal. Batman declares he will venture to Apokolips and bring Damian back -- alive. It is later revealed that exposure to the crystal without some type of protective garb can prove caustic to the holder unless they hail from the New God race.
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