Kuria Raito

Kūkyo, more commonly known as Dark Phoenix by Phoenix, and in general known as Dark Entity, was a Elemental Warlord who in conjunction with seven others, ruled over half of Echo. At one point, she discovered the existance of Earth, and created a portal to link the worlds, and thus began the 8 Warlord's Invasion of Earth, which happened in the middle of the Reality Fantasy War. She was the last of them to fall in battle to Phoenix, as she was the eldest and strongest of the 8. Her spirit, as well as the other Warlords, were used to forge the Elemental Slayers, to combat and slay Elementals and elemental magic users alike.

Unlike the majority of her fellow Warlords, she only seems vaguely interested in the affairs of the world, and only does anything to suit own personal motivations. In addition, her actions were often targeted at very specific groups or locations, while the others would attack any and all human targets. These actions tended to be more or less a separate campaign from the others, which weakened their fighting force. It was only once the enemy came close to overtaking the Warlords did she truly finally join the Warlords in their efforts, at which time the battle turned into a stalemate, until the arrival of Phoenix.

Status - Sealed, Alive
Kūkyo is far from dead. If a wielder of her sword should fall prey to their emotions, she will gradually be able to take hold over them and eventually release herself from the sword that has long since bound her. If her power is ever completely released from Dark Slayer, it could mean the return of the 8 Warlords.

It is possible it was her doing that brought Kado back from Twilight, and perhaps even more likely, is that she is growing stronger off his rampant emotions, which could lead to her revival.

Unequaled Darkness
Her power over Darkness is absolute. Anything that hides within the shadows is well within her sight, and all shadows obey her will... even the shadows of the mind are hers to bend and manipulate.

Undying
Kūkyo is a pure embodiment of Darkness. It is almost impossible to destroy her, - permanently. The most that can be done is restraining her power within Dark Slayer - which has proven to be one of the only possible ways to deal with her for any given length of time.