A Cruxis Crystal (クルシスの輝石, Kurushisu no Kiseki?) is an evolved form of Exsphere in Tales of Symphonia which promotes the dormant powers of the body even greater. Most users of Cruxis Crystals are described as angels due to the wings they obtain by having the crystal.
Angels can use special combat abilities developed during the Kharlan War. One ability uses the body's mana to alter its metabolism and stop the body's internal clock. This allows the user to stop aging and become capable of living longer than elves. Possessing the crystal results in loss of natural human senses and responses, such as hunger, sleep, touch, ability to speak, and emotion unless the wearer is equipped with a Key Crest or "Rune Crest". At one point in the story, Colette Brunel becomes subject to the effects of the Cruxis Crystal, resulting in an increase of body strength, as well as improved sight and hearing. A very rare disease caused by a Cruxis Crystal is the Chronic Angelus Crystallus Inofficium. It occurs when the body of a Cruxis Crystal bearer rejects the crystal and takes on a crystallized form, but the odds of this are rationed at one in a million.
In Tales of Symphonia: Dawn of the New World, the Vanguard is persecuting both Colette and Zelos Wilder under official charges of treason, but their true motive is later revealed to be obtaining the Cruxis Crystal from one of them. Richter Abend discovers he can use it to extend his lifespan indefinitely, and by combining it with the "Sacred Stone", the stone that turns the body's mana into flames, he can become an eternal human sacrifice to lock the Ginnungagap.