MMA System: I Will Be Pound For Pound Goat - Chapter 1 - : Some Quick Cash

A great demon king who came from another world to conquer Earth. To save the Earth, Li Luyou could only first take care of this great demon king… a little girl proclaiming herself Her Imperial Princess.

- Description from Novelupdates

In the King’s game, the [King]’s order is absolute and has the power to create rules. As the owner of a special physique, Gu Huai was selected by the system to participate in the game. “Win the game and become the [King], and you can obtain whatever it is you desire.”

- Description from Novelupdates

[Ding! Dragon Monarch System has been activated.]
Aditya finds himself in the body of a 19 years old dragon. Aditya learns the misfortune fate of the former Aditya. Being a man from the 21st century, Aditya decides to change his fate.
Being married to the 7 goddesses of this world, Aditya walks on a path to prove himself to his wives and to his family.

"Goddess of War"
"Goddess of Alchemy"
"Goddess of Wealth"
"Goddess of Wisdom"
"Goddess of Lust"
"Goddess of Music"
"Goddess of Nature"
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Disclaimer: - The image used is not mine. If the author messages me, I will take down the image.

You take up a student career.

Student career upgrade to lv.7

Acquired skills: primary school knowledge, junior high school knowledge, high school knowledge.

You take the college entrance examination,

You got a perfect score.

Your basic occupation has been upgraded to lv.9, and the job transfer system has been activated.

You change jobs to become a scientist, you gain R&D skills

You use research and development skills to get space fortress construction technology

You use R&D skills to gain starship technology.

You are invincible.

- Description from novelbuddy