One Piece, Vol. 20: Showdown at Alubarna

Skypiea's ancient history — the war between the Shandians and the Skypieans — is told in full as Luffy's crew is drawn into a conflict centuries in the making.

• Author: Eiichiro Oda
• Genre: Action / Adventure / Shonen Manga
• Series: One Piece (Vol. 20)
• Format: Paperback Manga
• Publisher: VIZ Media
• Published: 2009-02-01
• ISBN-13: 9781421515144