Valkyrie's Shadow - Chapter 8Winter’s Crown: Act 1,

A man is reborn into the world of Avatar: The Last Air Bender as a waterbender from Katara's tribe. Best of all, he was the same age as her, and he had a system with him to help.He knows the future and a system that lets him continuously get stronger by completing quests or long-term missions, as well as giving him the ability to copy abilities from others for himself. He will become invincible in the world of Avatar, even more so than the Avatar himself.

Lu Changsheng, who traveled through time and became an apprentice in the Miaoshou Garden, originally wanted to work hard to be a generation of genius doctor who can help the world. But when he started to practice martial arts, he found that every time he practiced a martial art to perfection, he could improve his understanding.

Moreover, understanding seems to be able to improve all the time. Lu Changsheng wanted to know, where is the upper limit of comprehension?

Unremarkable: Slightly better than crap.

The posture of the middle man: obscuring everyone without knowing it.

Possesses great potential: Xiao He has just shown her sharp corners.

Qianlong in the Abyss: Flood Dragons Come Out of Shallow Water!

Praise from all sides: Show your sharpness, unstoppable!

Dragon and phoenix among men: The name of genius spreads all over the world!

Praise for centuries: Founding a sect and establishing a sect, calling the sect and being the ancestor!

A born sage: astonishing the past and the present, unsurpassed!

There is no one in all ages: there is no one before and no one after!

Top savvy: unspeakable, unseen, unheard!

…

The finished volumes of “Mage Profound Truth”, “Eternal Martial Arts”, “Longevity Seed”, “Old Master” and “Survival Seed” are all excellent works, produced by Lao Yue, they must be excellent!

- Description from novelbuddy

Ambrose Lu possesses the Eternal Longevity Body, granting him immortality and eternal life.Throughout countless years, he has traveled through myriad worlds, gained infinite experiences, and held various roles.He has been a leisurely Immortal Emperor, a tavern keeper selling wine, the mysterious leader of a sect known as the Carefree Sect, and a divine healer saving lives in his medical clinic.Additionally, he wields blade as the Green-Clad Sword Immortal, using his sword aura to sweep across the world!

This is a cliché story about two young people saving the world.