Basara is one of the Juunishinshou who specializes in archery. He can fire more arrows than usual (5 or so), all with accurate aiming. While doing this, his front is exposed. To overcome this, he prepares arrow traps that surround him, so an opponent cannot get close to him. In his ultimate attack, he fires his entire quiver with one shot (about 50 arrows). He was defeated by Sanada Yukimura, who sliced him in half.  His real name was Maro and he spoke in third person, causing confusion as to his name.

At the dawn of the 17th century, at the end of the era of civil wars, in a world of chaos, the epic Battle of Sekigahara was joined. One man emerged from the largest battle ever fought on Japanese soil; a terrible warrior of unspeakable power, he was nicknamed 'the unconquerable.' 
Kyoshiro is a peaceful medicine peddler who harbors the soul of an assassin. He accompanies a young bounty hunter across Japan in search of a murderer and on a quest to discover the terrible secret of his own identity. (Source: Tokyopop) 
 
Volume 38 contains the side story "'Michi' no Tochuu" (「道」の途中).

In the year 1600, during the battle of Sekigahara, warriors Kyoshiro Mibu and "Demon Eyes" Kyo - the legendary slayer of a thousand men - engaged in fierce combat. Both men disappeared when a meteor crashed in the battlegrounds. Four years later, Kyoshiro is spotted on a rural highway, acting as a traveling medicine salesman. He is captured by the female bounty hunter Yuya Shiina when she discovers that deep inside him is the dormant personality of "Demon Eyes" Kyo himself.
 
(Source: Anime News Network)