Three Evil Stars
There are three monsters who are considered the greatest and most evil Yokai in all of Koryo: the ghost of Sutoku Tennō (Emperor Sutoku), the nine-tailed kitsune Tamamo no Mae, and the dreaded king of the oni, Shuten Dōji. Together, these three form the Three Great Evil Yokai of Koryo.
King of the Oni-Shuten Dōji
The dreaded King of the Oni whose love of sake and puzzles is overshadowed only by his thirst for war, bloodshed, and brutality. During the First Great Yokai War, he formed a temporary contract with Saiha and fought alongside him and his Ayakashi. However, he fled during the final decisive battle along with the Kyotouryu: Guren Kaina that had been lent to him. His wife Kurozuka fled from him after he caught her attempting to steal Guren Kaina while he slept.
He has no interest in the balance between human and Yokai. He fights only for personal benefit and to spread chaos. With Saiha gone, he'd gladly fight alongside the Yonkishi, but if suitable incentive was presented, he would also fight for the humans.
Kyuubi Temptress-Tamamo no Mae
A wicked nine tailed Kitsune whose magical abilities are matched only by her trickiness and lust for power. Originally one of Saiha's Ayakashi, her lust for power led her to attempt an unsuccessful coup against him. Saiha banished her from Tengoku and she spent the next few decades infiltrating the courts of large cities and manipulating their leaders.
She held orgies in the palace gardens as she used her beauty and charms to dominate leaders, encouraging cannibalism, murder, and urging them to commit other unspeakable horrors. Her fondness for watching and inventing new forms of torture were legendary.
Unable to tolerate her atrocities, Saiha sealed her into a boulder that would become known as the Sesshō Seki, located in the vicinity of Tochigi Forest.Even though she had been sealed, Tamamo no Mae's wrath permeated through the surrounding area, transforming it into a desolate lifeless field filled with toxic gasses and the skeletons of animals who strayed too near. Any living creatures who touch the boulder die.
Should she be freed, Tamamo no Mae would seek vengeance against Saiha. With him gone, she would join the Yonkishi and wreak havoc across Koryo.
Emperor of Onryo- Sutoku Tenno
The oldest and most mysterious of the San Dai Aku Yokai, Sutoku Tenno is a wrathful spirit full of rage for the living. He views the living as deplorable for allowing spirits to die with regrets, and makes every effort to distance himself from the living. Sutoku Tenno's haunting grounds vary as he drifts from place to place, haunting old battlefields, graveyards, and areas where death hangs thick, though he is most often seen in the Jukai, the O-Mizu, and the western ridges of the Kita-Yama.
Due to his reclusive nature, not much is known about Sutoku Tenno other than that he is the most neutral of the San Dai Aku Yokai, preferring to hate and curse the living from afar.
Like Shuten Dōji, Sutoku Tenno could fight for either side in the war to come.
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