DewPrism is a relic created by Valen, one of the Aeons. It has an enormous power which can reshape reality to its users wishes.
DewPrism was created by Valen, one of the strongest of the Aeons. DewPrism, unlike any other relic, can reshape reality. This means it can resurrect the dead, change time and, reshaped the universe to one's liking. If its powers are used, it could bring disaster or destroy the world.
Valen created the relic so he could change the universe to his own image, but he was destroyed in the process. The relic was then sealed so that no one could use such power for their own selfish ambitions. The East Heaven Kingdom was entrusted to keep such a dangerous relic from anyone who wished to use it.
In the quest, both Mint and Rue search for the relic so they can use it for different reasons. Mint wants to use the DewPrism for World Domination while Rue wants to use its powers to resurrect Claire.
Another one who wishes to use its powers is Doll Master, who wants to resurrect his master, Valen, so he could finish his mission.