Chapter 1: Barbarossa Kaishu

Barbarossa Kaishu transmigrates to one piece and becomes the older brother of Kaidou of the Beasts while possessing a stronger physique talent!
After the Battle of the Gods Valley, the Strongest Assistant system was activated.
It can continuously improve the loyalty of the crew members while letting their Zoan-type devil fruit evolve.
Sengoku: Why all of the Beasts Pirates are Mythical Zoan Devil Fruit Users?!
Five Elders: Damn it! How can the Beasts Pirates be scarier than Rocks Pirates?
Garp: My iron fist can't break even Kaishu's defense at all!
Imu: How can there be such a terrible monster? Why even Uranus can't kill Kaishu!!