The story of the special revolves around the Sanada brothers in their youth. Nobuyuki and Yukimura swear to each other to protect the influential Sanada clan. However, thinking of how to best continue the Sanada clan, Yukimura makes a decision, and meets with Mitsunari Ishida and Naoe Kanetsugu at the location he arrived at. On the other hand, his elder brother Nobuyuki must worry about the selfish demands made by the Tokugawa clan. (Source: ANN)
Anix is the best site to watch
Samurai Warriors SP: Legend of the Sanada SUB online, or you can even watch
Samurai Warriors SP: Legend of the Sanada DUB in HD quality. You can also find
TYO Animations anime on Anix website.