One Piece: With Sign-in System Novel

Ron awakens in the One Piece world on an isolated East Blue island, bearing an extraordinary gift: a sign-in system that unlocks formidable abilities at every destination he reaches.

His inaugural activation grants him the legendary Sun Breathing Technique and enhanced vitality. From Shimotsuki Village's humble beginnings to the celestial heights of Skypiea, through the fortress of Enies Lobby and into the chaos of Marineford, Ron systematically claims rewards that elevate him beyond ordinary limits. Raikiri—among the 21 Great Grade Swords—falls under his command, alongside mastery of Armament Haki and Observation Haki.

When Ron arrives at Marineford during the Summit War's climax, the world's strongest combatants—Four Emperors and Marine Admirals—find themselves paralyzed by his arrival. His dismissal is casual: "Don't mind me. I'm just passing through."

Follow Ron's expedition across the Grand Line as each location visited strengthens his resolve and power. What unfolds is not merely adventure, but the genesis of legend itself.