Cruxis Crystal

Cruxis Crystals are an evolved form of Exsphere which promote the dormant powers of the body even further. However, this also means the loss of all human requirements such as sleep, hunger and thirst, and of all emotion, unless the wearer is equipped with a Key Crest or Rune Crest. At one point in the game, Colette becomes subject  to the effects of the Cruxis Crystal, resulting in an increase in her bodily strength as well as improved sight and vision, but also resulting in her ignorance of all else.

Chronic Angelic Crystalus Inofficium
A disease which is said to afflict one in a million people. It is the result of rejection of the Cruxis Crystal, and causes the body to slowly crystalize. The only way to stop it using a Rune Crest.