Dragon Ball Roshi - Chapter 248: Matters on Earth

Kai of the Sorcerer’s Tower is one of the last mages left, barely surviving in a world ruled by creatures of the dark — where the era of mages ended, and most of the lands got contaminated with dead mana. To save his world and fulfil his master’s last wish, he put himself through a forbidden ritual, risking his soul being ripped into pieces to make his way into the past. In an era with abundant mana — an era yet to enter the Golden Era of Magic. Things go wrong, of course, as they always do, and he finds himself thousands of years before the world fell to mana contamination — in the body of a young lord, Arzan. All is not well, though, as the young lord was murdered by someone right at the cusp of a beast wave threatening the territory, while larger threats loom on the horizon. There was a lot to do for Kai to regain his former strength in this time of primitive technology, but then again, he might just be able to change that.

When he woke up, Lin You found that the world had changed drastically.

Monsters of all races roar and bombard wildly, field magic cards form a deep sea out of thin air, royal tombs, skyscrapers, and trap cards are infinitely possible.

Duellist colleges and universities all over the country are rising, and the miracle secret realm is full of dangers.

This is a world where all people chase cards, and the era of card duelists shines.

- Description from novelbuddy

For others it takes dying and reincarnating for them to get a system but what happens when you get one without dying?

Aron Michael is an average student set to graduate within a week, but he was expelled for a random reason. Due to that, he had heavy student debt and no diploma to help him earn the money to pay it back. But one day he got a system that called itself the [Advanced Tech System].

Follow the story to watch him develop from your average Joe to him being the owner of the largest company in the world.