MTL - The Secret of the Seal - Chapter 13 Tianyuan Dan!

Reach the peak of immortal cultivation and become able to run amok without fear! Use the power of martial arts to rule the world and defeat heroes! The weather changes at the whim and wave of a palm. He who cultivates both immortal techniques and martial arts, who could possibly defeat him! Xiao Chen is a shut-in who purchased a ‘Compendium of Cultivation’. Soon after, he crossed over into the Tianwu World, a world ruled by martial arts. He then refined pills, drew talismans, practiced formations, crafted weapons and cultivated the Azure Dragon Martial Soul that had not been seen for thousands of years. This is a story that tells of an exciting and magnificent legend!

Qiao Chen was mysteriously transmigrated to the interstellar era. As an adult from his original world, he was forced to grow up all over again in this new one. Now, out of nowhere, he was requested (forced to take on) with the inexplicable task of jumping from world to world to save the high general’s soul.

Throughout his journey, Qiao Chen finds that these worlds and bodies he’s jumping in and out of are his previous reincarnations. Whether or not these all culminate into coincidences or a predetermined destiny, there’s things that must be done while completing the main task:

-Avenge his past life

-Take revenge

-Fulfill past regrets

-Realize those lost dreams

-Make up for past failures

Since God has given him these opportunities to rewrite his fate, why wouldn’t he be pleased to start-over?

- Description from Novelupdates

Xiao Ran transmigrated to a fantasy world. As a dungeon guard in the Celestial Dungeon, with a special floor called the Purgatory meant for powerful demons and martial arts experts, he faced a huge challenge from the start. The Eldest Princess acquired a forbidden martial arts technique and was banished to the Purgatory. However, no one was powerful enough to restrain her. All the dungeon guards were defeated. Xiao Ran stepped up and declared, “Your Highness, it’s better for you to behave yourself on my territory” and effortlessly subdued the Eldest Princess.

He progressed from imprisoning the Eldest Princess to delivering the Great Xia Kingdom from the evil clutches of various demons and evil martial arts experts.

…

Xiao Ran was the mastermind behind the scenes.

Jacob Steve, an Old Man, died at 116 after living a whole life.

But Jacob always had a dark side, which he always suppressed and hid from others.
However, in the later years of his life, when death was inevitable, he understood there wasn't any point in having wealth, knowledge, or desires if you couldn't have a life to enjoy them.

He became obsessed with fabled immortality and devoted his reaming life to extending his fleeting lifespan, but just like any other failed.

However, he mysteriously got another chance at life and found a way that led to fabled immortality.
But he was also forewarned that the way led to it was filled with blood and darkness!

In the end, Jacob chose it anyway with no way of going back, and it was also the start of his suffering and his icky, brutal journey toward the 'Immortality' he wanted so badly!