A 1.5-Billion-Berry Bounty: The World Government Begs Me to Stop Making Devil Fruits

[One Piece] + [Technology] + [Comedy] Su Yousheng, a navy genius scientist, defected after witnessing Kuma’s modification experiment. He has a secret ability to extract blood and use it to create Devil Fruits with no side effects. Before defecting, he had already secretly collected blood samples from the entire navy high command. Now he takes this forbidden “arsenal” to the New World and builds up his forces, recruiting deserters with Kizaru’s Glint-Glint Fruit and winning over pirates with Akainu’s Magma-Magma Fruit. Step by step, he creates a third force that both the navy and the Four Emperors fear.

P.S. There’s a stretch in the middle about everyday life aboard the ship, so the plot may get a little confusing.