Saving 80,000 Gold in an Another World for Retirement - Chapter 219

A guy became a brother of Iron man and got the ability to extract genes from anyone. Lets see how he changed the Marvel World

- Description from Novelupdates

The end of all worlds approaches.

The Demon King Order harvests lives from all manners of living beings.

Within this darkness full of despair,
A single person escaped from space-time, returned to before the world collapsed, determined to change the fate of the past.

But as time pass, he gradually finds out that the Apocalypse isn’t quite as simple as he thinks…

- Description from novelupdates

Daiki Tsukasa transmigrates to a world of everyday anime crossovers.At the start, he purchases a Special-Grade Cursed Object, activating the Great Collector System.As long as he collects valuable items, he can receive rewards.『 Congratulations, host, for collecting the Special-Grade Cursed Object — Sukuna's Finger. Reward: Innate Domain — Malevolent Shrine! 』『 Congratulations, host, for collecting the Yukinoshita Family. Triggered Triple Bond. Reward: Immortal Dual Cultivation Technique! 』...Miku Nakano: I was here first! Get lost, you vixen!Yukino Yukinoshita: Could you stay away from my sister?!Iroha Isshiki: Senpai! You won't abandon your cute kōhai, right?۞۞۞T/N: Be advised that characters and powers will be used, but not necessarily in the exact order, logic, manner, or arrangement that occurs in the original. Some stories will obviously be changed to fit into this mixed world with so many characters.

After experiencing heartbreak from being abandoned, he enlisted in the military.

And then, he became a war hero.