The Inheritance Succession Arc is an anime-exclusive arc that details the happenings when Tsuna and his Family that went to the future travel back to the past (except Basil) to get stronger with the help of the Arcobaleno and obtain the Vongola 's true power. In the past, the Arcobaleno, with the help of Yuni, summon the First Generation Vongola Famiglia led by the Vongola Primo, where they will then help the current Vongola Generation prove themselves worthy of inheriting the legacy of the Vongola.