Sailing at Sea: The Breath of the Day at the Start

Ron transmigrates to the world of One Piece and becomes a child on a remote island in the East Blue.
By linking to the check-in system, you can earn various rewards simply by checking in at different locations.
Sign in at the start of the game to receive the reward: [Health +10, Sun Breathing Technique].
Sign in at Frostmoon Town to receive the reward: [Great Grade Sword 21 - Lightning Blade]
Sign in at Sky Island to receive the reward: [HP +10, Ultimate Mind Network].
Sign in at Enies Lobby and receive the reward: [HP +10, Armament Haki].
Check-in at Windmill Village, Loguetown, Sabaody Archipelago, Fish-Man Island, Amazon Lily, Impel Down, Mary Geoise...
……
Marineford War.
When Ron appeared in Marineford.
Everyone present, from pirates and emperors to marines, stopped fighting.
Ron waved his hand: "Don't worry about me, you guys fight. I'm just a passing traveler."
(This book...)