Soul Gem

The Infinity Gems were said to be the essence of the primordial entity Nemesis, whom split itself into six gems, eons ago. Nemesis chose to end its life, rather than live as the only sentience in the universe. The small emerald green babble known as the Soul Gem revealed that it was a sentient life-form possessing vast cosmic abilities. These abilities have been transferred over its host. The Soul Gem appeared in the possession of the servant of Lord Chaos and Master Order known as the In-Betweener, although it is unknown if he was the first host to ever possess the Soul Gem.