|Devon Aoki cast as Katana|
One of the best things about CW's Arrow is the fact they're not afraid of introducing other DC Comics characters into the show. The latest example is the casting of Devon Aoki (2 Fast 2 Furious, Sin City) as Tatsu Yamashiro aka Katana for the upcoming season.
Katana is a highly trained martial artist and swordsman. She wields the Soultaker sword who legend states consumes the souls of those it kills. According to Deadline, this regularly recurring role is described as essential to Oliver's development. She'll been seen in flashbacks as one of his mentors.