Fairy Heart

Lumen Histoire is Fairy Tail's greatest secret.

Description
Lumen Histoire is located in a secret underground room in Fairy Tail's original building. This secret is only known by Fairy Tail's Master and is passed on to each new one successively. Purehito showed it to Makarov when he became Master, and in turn he showed it to Gildarts Clive when he tells him that he wants him to be next Fairy Tail Master.