After Divorce, Hidden Marriage Husband Became Addicted to Me - Chapter 620 - 385:

A teenager who unexpectedly gets transported to the modern world from ‘the world of the immortals’ . He finds himself in the body of an ordinary guy. He wants to go back to his world and for that, he will have to practice to get stronger and investigate the reason why and how he crossed through to this world.

- Description from Novelupdates

Mark is a genius military weapon designer who was kidnapped by a mafia gang after refusing to work for them.
They forced him to design unique weapons for five years, until one day he successfully escaped only to get shot by his trusted comrades.
*Ding! You awakened a weapon system.
When he opened his eyes, he was in a different body and in a different world.
"You want to kill a wild boar without being detected? Forget about bow and arrow. Here, I present you this sniper rifle."
"You want to kill a horde of goblins from the sky? Forget about those flying carpets and brooms. Here, I present you the fighter jet."
"You want to kill a dragon? Forget about taking the help of the S-class adventure team. Here, I present you a nuclear bomb."
Join Mark Spencer/ Lu Zhen as he brings the whole world to its knees with the help of his weapon system.
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Note: Author isn't born in an English-speaking nation and has no editor either. So, please be understanding if there are any grammatical errors.
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I possessed a reliant villain who was in debt and clinging to the heroines.“Why did I give all these good things to others?”From now on, I will solely focus on my own growth.After stopping these villainous acts,the heroines’ reactions were strange.

To rise from defeat; to revive amidst the dissipation.