The Staff of Elements was a powerful item capable of manipulating the magical abilities of mortals.
It had three main functions: To store supernatural abilities, perfect the output strength of said abilities, and then granting it to those deemed worthy.
The staff was exclusively used by The Dragon Cult to store elemental based abilities. These powers would then be granted to a group of a worthy few, to train with and use, if seen fit by the leader of the cult.
The Staff of Elements was an object of awesome power, but more importantly a religious symbol of the Dragon Cult's faith.