One Piece, Vol. 21 by Eiichiro Oda

In this volume, the Straw Hat crew and their allies race to stop a shadowy criminal organization from plunging a desert kingdom into civil war; amid sandstorms and ruined cities, Luffy faces the organization's mysterious leader in a brutal final showdown, allies display courage and sacrifice to expose the true conspiracy, and the arc reaches an emotional resolution as the princess makes a painful choice about her country before the crew parts ways and sails onward toward their next adventure.

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