I Alone Level-Up - Chapter 6

When an S-class elite assassin-raised captain of a special ops suicide squad comes home from a high-stakes Africa mission, he finds himself offered something that could potentially set him up for life- a curious assignment that he could use to finally exit his days of war and slaughter.

The god king of Xiaoting in the upper realm fights down, and the spirit of the mixed dragon spirit is reincarnated on the earth, runs rampant in the city, and then fights in the sky.

Those who obey me prosper, those who oppose me perish!

- Description from novelbuddy

When I was 15-years-old, during the year that I graduated from middle school, my father told me this.

Anyone who could construct a stable Spell Model could become a Wizard — that was the Wizards’ ultimate secret! Having been given a new life as the son of an aristocrat and armed with a super quantum computer from his past life, Spell Models came as easily as breathing to Merlin. With this overwhelmingly huge advantage, would Merlin become the greatest Grand Wizard of all time?

- Description from Novelupdates