His real name is Eishu Retsu (烈永周, Retsu Eishū; Chinese pinyin: Liè Yǒng-Zhōu). In his training days in Heilongjiang, Bailin Temple he was called Shaoron Retsu (烈小龍, Retsu Shaoron; Chinese pinyin: Liè Xiǎolóng).
A Chinese martial arts master, trained in China and became the heir to his Kung Fu style in his temple. He was a man of great discipline and skill. He was sworn to uphold the honor and pride of the ancient art of kung-fu although in time he learns to appreciate the diversity of all the worlds martial arts rather than claiming Kung Fu to be the strongest as he had done throughout the entire tournament.
Despite his great knowledge in his style, he does not open his mind to the possibility of learning from other disciplines at first, but after striking up a friendship with Katsumi Orochi post tournament he appears to want to teach as well as learn at the Shinshinkai Dojo.
After learning that Musashi Miyamoto had been reborn, Retsu chooses to challenge him in order to learn the full potential of a blade. It is during this fight that he is killed, as Musashi overcomes the defensive Shaori and cuts through most of his internal organs and his spine.
Retsu Kaioh is a very well-built man, whose long black hair is tied up into a single pigtail. His eyebrows are somewhat thick and reminscent of small scythes. In a fight, Retsu will most of the time be dressed in dark blue/black shaolin monk pants and boots, with no shirt on. Occassionally however, he may dress smartly or casually.
After his battle against Pickle, Retsu's leg is severly damaged, forcing him to wear a pegleg instead.
This section needs a lot more details.
Retsu Kaioh was the single best apprentice of Kaioh Ryu and by the time of his fight with Musashi Miyamoto, he was one of the most proficient martial artists of China, just below Kaku Kaioh in terms of skill. While participating in the Underground Tournament, Retsu fought Baki and awakened his "Hanma spirit". Later, as the Five Deathrow Convicts roam free in Japan, Retsu continiously persuedes Dorian Kaioh and eventually has a fight with him, which Retsu effortlessly wins. The aftermath of their short battle leaves Dorian with serious brain trauma, causing his mentallity to revert back to that of a child. During the Raitai Tournament, Retsu and Baki are seen observing and profusely commenting on the battle between their superiors- Yujiro Hanma and Kaku Kaioh. In the fourth series- Baki-Dou, Retsu went up against Musashi Miyamoto in a deathmatch. Though he put up a good fight against the legendary swordsman, him overestimating his abilities early on leads to his unsightly death.
Retsu was an accomplished fighter who attained the rank of Kaioh, strong enough to beat Mount Toba in less than a minute and Katsumi with only one punch. His most famous feat was pounding a boulder into perfect ball shape. Retsu is also very good at using weapons. He can throw shurikens at a precise rate, using alcohol as a flame thrower, fighting with a wooden stick, using ropes to bind opponents or travel, and even using a 9-section whip.
Retsu fights with dirty tactics sometimes, such as using his hair to blind his oppenent, or using his shirt to throw dirt as projectiles. Retsu once used the mushin, a mental state in which he automatically uses his techniques and reflexes to defend and fight. Despite this, he was defeated by Pickle's strength. According to Yujiro Hanma, Retsu was able to awake the "Hanma spirit" in Baki Hanma.
- Spinning Lotus - an unusual technique from Chinese Kenpo.
- Sunkei - powerful one-inch punch developed in Ancient China.
- Invisible Squash
- Toe Use
- Windmill Punch
- Crushing Fist
- Mach Punch
- Defensive Shaori
- Roll Kick