The Light/The Other Side

The Light, or The Other Side is referred to as the other world where the power of Alter originated, a place bathed in psychedelic light. One can achieve the light when encountering "The Crystal" or by exceeding the limit of their Alter through immense force of will.

History
The Light/Other Side was first experienced during a disaster that occurred in Japan twenty years ago called the Great Uprising, which devastated part of the archipelago and ripped apart a large of land and raised it higher into the atmosphere. This portion of land became known as the Lost Ground (island) and seen as the birthplace of Alter Users, a small generation of humans and animals that make up two percent of the global population, but as the years progress, that number has increased.

Kazuma first obtained the power of the Light/Other Side when he went into the Alter Forest in search of greater power to better fight Ryūhō Ryu. In his search, he encountered and fought "the Crystal", and tore out its backbone. Being from the Other Side, the piece of "the Crystal" infused into Kazuma's arm, transforming his Shell Bullet and increasing its power to greater heights.

During a battle between Kazuma and Ryūhō Ryu, a second Great Uprising occurred and drew the attention of the Mainland, desiring to exploit the power of the Other Side for economic gain. To do this, they send their refined Alter User, Kyōji Mujō, to the Lost Ground, but as he obtains greater power after absorbing The Crystal, he develops delusions of grandeur and defects, wanting the power of the Other Side for himself.

During Kazuma and Ryūhō's combined assault on Mujō's stronghold. Ryūhō engages in a heated battle with Martin Zigmarl, and unlocks the power of the Other Side to become one with Zetsuei. During his fight with Mujō, Kazuma unlocks the power of the Other Side and materializes his Shell Bullet into armor. After being sent into the Other Side Kazuma, Kyōji Mujō became mutated after harnessing too much of the Other Side's power, but he was soon defeated and destroyed by Kazuma.

As a final attempt to gain control of the Lost Ground, the mainland government sends their army of refined and artificial Alter Users, but they are defeated by Kazuma and Ryuho, and as the series comes to a conclusion, the power of the Other Side is still something to be desired by the mainland government.