Mobuseka:Leon's Adventure - Chapter 73: Angelica(2)

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.

Enigmatic hands, spectral frame, and one cunning strike just like the swing of the Grim Reaper. The Supreme Assassin takes on the mystical world, and how his legendary tales sets off, progressively ascending the altar to becoming the best.

- Description from Novelupdates

A child was born unable to cultivate Inner Strength. In order to gain his father's attention and regard, he resolutely chose the painful and difficult path of cultivating Outer Strength. As spring gave way to autumn, time flew by, and the child grew up... he became a young man. What truly changed his destiny was a mysterious Crystal Stone formed from a meteor—the Meteor Tear. This Meteor Tear, unbeknownst to the young man, merged into his body, and like a caterpillar transforming into a butterfly, the young man metamorphosed... And with that transformation, everything changed. And his father finally came to realize the astonishing strength of the son he had never truly invested his Heart Power in...

After dying from betrayal, Thomas reincarnates as Jolthar Kaelzhar, the neglected son of a powerful clan, just after his brothers kill him. With Jolthar's memories and the blessing of Qalena, Thomas vows to rise from his lowly position and claim power in his new life.

By the time I reached thirty, I hadn't managed to provide any of the happiness I wanted for my wife.I also still couldn't become the support my parents relied on.At this turning point in my fate, my income suddenly began to increase randomly.(A daily life tale in a wealthy family setting, featuring a single female lead and no harem.)