The National Goddess Reborn - Chapter 239 - Beat him Into Submission  

Once through the pirates, Lu En became the son of Monkey d Dragon, a grandfather named Monkey d Karp, and an unreliable and neurotic younger brother named Luffy.

Fortunately, the ghost back system is activated!

The completion of the ghost back is 10%, and the training effect is increased by 100 times!

The completion of the ghost back is 20%, and the training effect is increased by 1000 times!

…

One day, Lu En, a ghost-backed master, appeared in front of Luffy who was shouting to go to sea, and made Luffy cry on the spot.

Luffy: “The pirates in the sea are all monsters like my brother? I don’t want to go out to sea!”

Garp: “For a long time, the two boys, Long and Luffy, with small arms and calves, I really doubt that they are not my sons and grandsons. Like Lu En, they are the grandsons of the old man!”

Warring States: “The strongest creature in the sea, land and air is Kaido? No, it’s Lu En!”

- Description from novelbuddy

This is a story about the protagonist getting the system, going crazy in the biochemical apocalypse, producing aircraft and tanks, destroying zombies, saving good people and killing bad people.

- Description from novelbuddy

A serious accident caused the protagonist’s brain to have an unusual mutation. This changed the brain development that it opened the door to a mysterious universe. Not only he obtained a ‘god-like’ powerful telekinetic control and mental perception, he also had an abnormal analysis and memory capability comparable to super computer. Having such super brain, his rough life began.

Brain development progress 10%…….20%……50%….80%…. …100%

- Description from Novelupdates