In shogi, the Kamaitachi opening (かまいたち戦法 kamaitachi senpou) or Eishun opening (英春流 eishun-ryuu) is an uncommon flexible opening. It was invented by amateur shogi player (鈴木英春). The opening can be played against Ranging Rook or Static Rook. Kamaitachi was named after kamaitachi (鎌鼬), which is the weasel-like mythological creature associated with whirlwinds that cut humans with sickle-like painless, bloodless wounds without their knowledge.