|Manga Debut||Chapter 231|
|Anime Debut||Episode 156|
The Helper's Book (助太刀の書, Sukedachi no Sho) is a small, blue book that Basil found next to him when he first arrived in the future. Various things are written inside, some of which, according to Basil, are instructions about how to use Box Weapons, the location of the Vongola Base, the battles that have taken place in the future, and information on the enemy, Byakuran. During the preparations for the final battle with Byakuran, when Gamma explained about Alfin's power to communicate with other Box Animals, Basil said that the Helper's Book had some info about this fact too. Basil stated that the one who wrote the book gave him orders through the written instructions to assist the "young Vongola." Basil also mentioned that it was a top-secret book and, if necessary, it must be burned to remain secret. He once said to Reborn that every time he read it, his Japanese samurai spirit woke up within him and thrilled him. The book has Sky Dying Will Flames at the top working as a seal. Reborn said that it was authentic, meaning that someone with a Sky-attribute Flame wrote it.