Here, I am with a Ninjutsu Densho from my private collection called the: Iga-ryu Ninjutsu Kakushi no maki. This is an official reproduction that was created from the original - which is located in the Iga-Ryu Ninja Museum.
This densho is said to be written in the 1500’s by Kawakami Hinokazu. This Densho does go by different names because of different translations. The other names attributed to this Densho are: Iga-ryu Ninjutsu Inka no maki as well as Iga-ryu Ninjutsu Kakurebi no Maki.
The importance of this text in the ninjutsu community is that its significance lies in its inclusion of shuriken methodology, offering a counterpoint to the prevailing assertion that ninja using shuriken are largely a product of modern embellishment through media such as manga and anime. This false propaganda of ninja not using shuriken is simply not true and is not historically accurate.
While major classical texts like the Bansenshukai (1676), Ninpiden (1560) and Shoninki (1681) make little or no explicit reference to shuriken as a formalized component of shinobi practice, the presence of such techniques in this lesser-known scroll suggests that regional variation and specialized methods did exist within the broader spectrum of historical ninjutsu.
This Ninjutsu Densho does invites an understanding: that shuriken, while perhaps not a specific secret weapon to the ninja arsenal, were, in fact, a part of the tactical repertoire in certain ninja lineages during the late Sengoku period. - Soke Anshu
