In the vast world of Io, everything is composed of the seven elements of fire, water, wind, earth, light, darkness, and life. In ancient times, various elemental civilizations fought for the legendary "Key to Origin" and broke out in world-destroying wars, which led to the decline of civilization and the loss of the Key to Origin. Today, the world is slowly recovering from the ruins, and new civilizations are sprouting on the ruins of the past. The young man Luo Qianshan is gifted with the ability to resonate with many elements and even create an "Elemental Soul" that contains souls. He unexpectedly discovered clues about the "Key of Origin", but was involved in a conspiracy that spanned thousands of years - a forgotten ancient civilization was trying to regain the Key of Origin and enslave all elemental creatures. Luo Qianshan must gather allies from all elements, explore the Lost Temple, reveal the secrets of the elements, and finally become a true "Elemental Soul Caster" to prevent the catastrophe from happening again, and use the Key of Origin to open a new era.
