Alchemy Ocean's Pirate King
Magic takes the world by storm while the protagonist is lost at sea for 9 years.
Atlus is a 15-year-old boy who engrossed himself in storybooks and bizarre training schedules for the time he was stranded on a legendary ship. He is ready to explore the world and conquer the nine seas.
But the kids of his generation who grew up on land live and breathe magic!
On top of it, he leaves too many loose ends while escaping from the navy. He has a vague idea of why he is wanted. However, even the top officials only know bits and pieces about the 20 ships identical ships that disappeared 9 years ago.
The empire won't stop until they captured him, and he won't stop until he is the strongest person who freely roams the world.