Vainqueur the Dragon - Chapter 11: Multiclassing

What does it mean to be invincible?

Many Sword Gods exhaust their entire lives attempting to cultivate a single supreme sword intent, yet Yang Xiaotian has cultivated fifteen!

For millions of years, no one has been able to cultivate the Primordial Heaven Destiny, but Yang Xiaotian has cultivated fifteen of it!

Throughout countless eons, no one has been able to cultivate the Primordial Universe Holy Fruit, yet Yang Xiaotian has cultivated fifteen!

Across the vast expanse of time, only the rulers of heaven and earth could cultivate the Eternal Divine Body, yet Yang Xiaotian has cultivated not only the Eternal Divine Body but also the Primordial Heaven Destiny Divine Body, the Primordial Universe Divine Body...

Leon is an average high school student who likes to watch anime and read novels.
He's about to cross the street, only to be greeted by a truck and died.
But, he got reincarnated as Uchiha yet dead again because Itachi killed him.
Leon got reincarnated again as the grandson of the recovery girl.
He got kidnaped and tortured by All For One.
After his third death, he got reincarnated as a son of Bibi Dong.
In this fourth life, he wants to change his fate to become the strongest.

Note: Please read the tag before reading.
- English is not my first language, so there would be grammatical mistakes in this story.
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An Individual from Earth finds themselves in the Shinobi World, equipped with a Scientific System. From that moment, he delved into scientific research far ahead of its time.

As a promise, he went out into the world as an assassin. 3 years later, after becoming the Supreme Assassin, he gave up on everything he had and returned to the ranks of ordinary people. But one day, Kismet, a mystical game created by the National Research and Development had appeared.