From A Stronghold NPC To The Final BOSS - Chapter 985 - : Ancestor devil, Rahu!

Zhong Li, an orphan in the 21st century, was wondering how to collect the fees for his college study on the street, when he was suddenly hit by a car, which threw him into a river. An orphan’s disappearance would not bring too much attention to the world, but this accident gave Zhong Li another chance of living a glorious life in an immortal world. When he woke up, he found himself lying in a magnificent yet strange palace built of all gold, but had no door. An immortal claimed to be his savior and wanted to train Zhong Li with all of his cultivation methods, only because he was too lonely and wanted a disciple to keep him company. When Zhong Li finished his study, the master would tell him how to go out of the palace. Zhong Li never thought that the path to immortality would bring him to the fate of becoming a dragon.

- Description from Novelupdates

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

In a single day, a global calamity wipes out humanity, leaving their souls adrift in an endless void.An enigmatic entity, responsible for the catastrophe, offers a twisted mercy: reincarnation into a deadly“King's Game.”Every soul from Earth must choose a character card to determine their new form and fate.Chaos erupts as billions scramble for power. Some snatch weak cards in haste, while others luck into formidable ones.Su Ping, caught in the frenzy, watches desirable roles like Goblin King, Blood Goblin King, and even Succubus King vanish.Desperate, he claims the only card left: Dark Dragon King.To his shock, this “lowly” dragon bloodline ranks among the top 1000 strongest. As Su Ping finds himself in a treacherous cosmo's where every player is a king vying for supremacy, he wonders:If a dragon is this low, what monstrous powers lie at the top?