Those Classmates who Suddenly Disappeared - Chapter 17 - This is really hard to explain

What would you do if you were told you only had five years to live?Aster Mistral, suffering from an incurable congenital “disease” that saps life force out of his every breath, decided to fight with all his might. Waking up into the future, 2,500 years later, he embarks on a quest to find a cure for his ailment!“My target! To find the Panacea on the 1,000th floor of the dungeon!”Together with trustworthy allies, he forges a path of blood and corpses, building his foundation and increasing his level! However, he can’t stay in dungeons all the time, as he has a duty to fulfill.“To raise the human DNA average of the world, the government wants my seeds?!”Follow Aster on his laidback journey of fighting monsters, courting girls, escaping adversaries, and discovering secrets about himself!

There was once an immortal cultivator fighting for the fate of human beings. Unfortunately, he failed that time; but fortunately got another chance as he was reborn once more as a human, on the earth of 5,000 years ago. With a second chance, he not only would embark on the road of saving all mankind, but also would retrieve his human nature on the new journey that would last for 5,000 years.

- Description from Novelupdates

He was The Greatest Talent in the Nine Hells Realm.

Shen Zhenyi began to practice his sword when he was four years and two months old.

At the age of seven, he studied the Ten Thousand Sword Sutra. By the age of eleven, he fought against the Yudao in Shangqing Palace. In an instant, he unleashed one hundred and eighty-five sword strikes, making it impossible for anyone to retaliate. The Yudao admitted defeat and deemed him as “The Peerless Genius.”

At the age of 14, Shen Zhenyi, with his Six Forms of the Ancient Sword, surpassed the swordsman Zuo Tianxing who was ranked among the top ten masters in the world, and won the title of “The First Swordsman of the Abyss.”

He now lies crippled. A fraction of the state he was in before. Or so they thought.

- Description from Novelupdates

Monsters, both human and beast, surrounded him. He needed power to survive this new world... but he arrived as a mortal.One moment William was at work. The next, he was captured by lunatics.He had never believed in the fantastical, but he had no choice after finding himself in another world surrounded by demonic cultivators trying to extract his soul. If he couldn't find an escape, his journey would end just as abruptly as it started.William was inches from death when a benevolent cultivator saved him from that fate. Seeing his pitiful state, the cultivator decided to give him an opportunity in the form of a tool: A system to guide him on the path of cultivation.William would use it to claw his way to the peak of the cultivation world.