Infinity Stones

The Infinity Stones were six powerful stones that each controlled a certain aspect of the universes. They were sought out by Ataraxia, who planned to unite them altogether within the Infinity Gauntlet to allow him to have full control over all of existence.

Locations
Each of the Infinity Stones initially appeared in the "first universe", but were scattered through the universes during the Big Bang. Most of them ended up in the Arc 1 universe on Earth sometime after the planet's creation, but a couple ended up in the Arc 2 universe. Each stone required something to happen in order to recover a stone.
 * Space Stone - Within the soul of a hero of light that channels the ability of spatial manipulation. Could only be obtained through the use of the Soul Stone. It was the fifth and penultimate stone to be acquired, being done so by Ataraxia after using the Soul Stone to extract it from Roach's soul.
 * Power Stone - Hidden in a secret compartment within the Gauntlet of Ataraxia. It was the sixth and final stone to be acquired, being brokered to Ataraxia by the heroes in exchange for sparing Roach's life.
 * Reality Stone - Sealed away in a lost temple in Yucatan, but could only be obtained by a being capable of recreating the stone from its liquid form. It was the second stone to be acquired, being done so by Gruntijackal and Richtofen.
 * Soul Stone - Within the Summoning Key, which was fused into the Harbinger's hilt by Roach. However, the seal could only be broken with the use of the energies of the mystical cavern within the Kilauea volcano on Hawaii. It was the fourth stone to be acquired, being done so by Xarcoh with the help of Omnitron.
 * Time Stone - Melted down into the Chronosteel blade of the Time Blade. It was the first stone to be acquired, being done so by Ataraxia upon destroying the Time Blade.
 * Mind Stone - Hidden away in the Colosseum in Rome, Italy, but could only be acquired by a being with an incredible high IQ who could solve the stone's puzzles. It was the third stone to be acquired, being done so by Amsel and Paul.