Back story characters who have direct knowledge of Kingdom Hearts.
Shiyoko
Shiyoko, the Fox of Death, guides souls (not Hearts) to the afterlife. He occupies a space between life and death called Hereafter, a space which he rules. He rarely gets involved with the affairs of mortals, so when he does- beware.
His powers are ranged from horrifically destructive, to bringing back the dead through a personal contract with him. However, people whos Hearts have been trapped by the Heartless or their allies cannot be brought back.
He is currently investigating the affairs of Kingdom Hearts from a distance, not yet sure if it requires his involvement.
Kratos Aurion
Kratos is a human who has lived for thousands of years via a powerful object called an Exsphere, powerful items crafted on the worlds of Sylvarant and Tethe'alla. As he traveled on a world called Derris Karhlan for thousands of years, he eventually became a friend of Shiyoko who fed him information about the mortal world and was given extra powers to travel between a network of worlds.
Nocturnal
Nocturnal is the Daedric Prince who resides in and rules over the Ebonmere. She is referred to as "Lady Luck", and has a system in Tameriel that allows one to become a "Nightingale", a follower of Nocturnal who will serve her within the Ebonmere after death. Shiyoko called upon her for her council as her current living "Nightingales" called upon her to help in a now spreading epidemic of Heartless upon the world of Tameriel.
Nayru
The Goddess of Wisdom in both timelines of Hyrule. Nayru has become aware of the Heartless epidemic through council between Shiyoko and those he has counciled with. She was contacted as she is notorious for being one of the wisest Goddesses, and was believed to have dealt with the Heartless in the distant past.
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Gannondorf
Gannon has been reincarnated time and time again, trying to steal the power of the Triforce in order to rule Hyrule. Every time, he has fallen short and been stopped by the hero time and time again.
However, he has somehow become privy to Kingdom Hearts, and has worked to unleash the Heartless throughout the worlds. His goals are quite clear, make everything his.
Alduin
Firstborn of Akatosh. Alduin was cast out of existence by the Elder Scroll at the Throat of the World long ago. However, he has finally returned. He returned with the Heartless in an effort to subjugate mortal kind throughout Tamriel. Its not clear if he brought the Heartless back with them, of if he brought them along with his return.
Alexei
From the world of Terca Lumeries, Alexei is the Commandant of the Zaphias army, the most powerful force on Terca Lumeries. He aspires to take the throne, and manipulates things behind the scene in order to make that happen.
He was made aware of the other worlds through another person who traveled to his land. While he has powerful Blastia at his disposal to fight his enemies with, he also has a powerful connection to the Heartless, who fuels his power almost limitlessly.
Alex
One of the main antagonists of Golden Sun, he is a powerful Water Adept who is clever and studious. He always manipulates things from behind the scenes, seemingly kind and merciful only to be vile and destructive later. He survived fighting the Wise One when the Wise One had the full power of the Golden Sun at his back.
Alex now aspires to unlock the power of the Golden Sun and pervert its power with that of the Heartless. However, his ambition doesn't stop there, he often seems interested in powers and abilities of other worlds with the intention of possibly possessing them as well.
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The Lady in the Lake
Since the beginning of time, she has given weapons to the heros throughout time. She goes by many names and has been appeared as many faces.
This time, she has come bearing gifts to new heros to fight the Heartless menace.
