One Piece 3D2Y: Overcome Ace’s Death! Luffy’s Vow to his Friends is a special anime that premiered in summer 2014, produced by Toei Animation.

About the production: the story comes from a manga, there is 1 episode of about 107 minutes and its current status is "finished".

Its main genres are action, comedy and fantasy, with themes such as Pirates, Anachronism, Male Protagonist and Super Power.

On AniList, One Piece 3D2Y: Overcome Ace’s Death! Luffy’s Vow to his Friends has an average score of 76%, a very good score, and appears on 24,158 users' lists.

This new TV special tells the two years of Luffy's training with Silvers Rayleigh in Rusukaina Island after the Battle of Marineford, which has never been told in the manga or TV anime. It also features a new villain named Burndy World who is known as "The Destroyer of the World" and has the power of the MoaMoa Fruit (its ability is still unknown). Luffy has to protect Boa Hancock from the new enemy who escaped from the level 6 of Impel Down. He is newly designed by the original creator of the manga, Eiichiro Oda. (Source: Crunchyroll)

Official synopsis from AniList.