The Senpumaru (旋風丸 Whirlwind Blade) is a long-handled, double-bladed sword with the power of wind. It appears in Onimusha 2: Samurai's Destiny. Jūbei Yagyū obtains this weapon from the Dragon Shrine outside the Misty Forest.
It's the fastest weapon Jubei can use, but not very powerful, very effective against fast and light genma. Attacking bigger and hardened fiends is almost suicide.
The Senpumaru attacks in a similar style to that of the Shippuu, which also has the affinity of wind.
Like Shippu, Senpumaru can summon forth a whirlwind around Jubei which sucks in and shreds to pieces any enemy caught by it.