Phillip, Yetvehrn, Cloudia, Silkehrn—those are the names of the four heroes chosen by the Keystones, four magical crystals thought to be the concentrated magic remains from when the Creator first created the universe. For centuries, they were passed down from generation to generation as a family heirloom of sorts.

It was prophesied that in a time of great peril, the Keystones would awaken and recognize a chosen four to inherit their strength—also known as the Keystone bearers.

1000 years ago, Princess Cloudia, the sole heir to the throne of the Kingdom of Jaune, saw a vision of four figures weilding the Keystones and standing up to the Monster Lord Echidna in a mighty battle. Taking with her the Thunderstone, she went on a journey to seek out the other Keystone bearers.

Firestone, Waterstone, Thunderstone, Earthstone—the four Keystones, when combined can unleash a power of similar magnitude to that of the Creator herself.

But when the four heroes finally battled with the Monster Lord, they were defeated.

Unknown to them at the time, there was one more Keystone that they had missed called the Dreamstone. The Dreamstone, as its name implies, could only be found in the Dream World.