4Koma Ninpoutou

The Ninjutsu Hatsudou 4-Koma Ninpoutou (忍術発動4コマ忍法刀) is a weapon invented by Sento Kiryu and designed for Kamen Rider Build's NinninComic Form. It is available to him in any form using the Ninjya Full Bottle. Its design is based off a katana, a four-panel comic strip, and a fountain pen.

Finishers
The 4-Koma Ninpoutou has four different finishers, depending on how many times the trigger is pulled; the panels light up in ascending order.
 * Clone Jutsu (分身の術): Build creates a number of clones of himself.
 * Fire Jutsu (火遁の術): Build delivers a flaming slash attack.
 * Wind Jutsu (風遁の術): Build creates a tornado and spins.
 * Stealth Jutsu (隠れ身の術): Build becomes invisible.