Brave 10

Brave 10 (ブレイブ・テン BRAVE10?) is a manga series by Kairi Shimotsuki, serialized in Media Factory’s Comic Flapper from 2007 to 2010. The series was resumed on June 15, 2011 and retitled Brave 10 S (ブレイブ・テン・スパイラル), serialized in Monthly Comic Gene. An anime adaption by Studio Sakimakura began airing on January 8, 2012.[1]

The original manga series is licensed by Tokyopop, though no volumes have been released as of 2012.
The series is based on the legendary Sanada Ten Braves, a group of ninja that assisted warlord Sanada Yukimura during the Sengoku period of Japan.