Ooyukiumi no Kaina: Hoshi no Kenja

After inheriting the company from their parents, siblings Yuuhi and Yuamu Oudou have started to work at Ultraterrestrial Trouble Solutions, an organization that hunts aliens. Although they have never encountered aliens before, Yuuhi is desperate to meet one as he believes that an alien has stolen his important item called the "Earthdamar." One day, while searching for extraterrestrial creatures, Yuuhi and Yuamu find a strange spot in the forest where many trees have fallen, forming a scenery similar to a crop circle. As they venture further, they discover a mysterious spaceship and enter it out of curiosity. To their surprise, they come across Yudias Velgear, an alien from the Velgear Star Cluster. As it turns out, Yudias is seeking to learn about Rush Duel—a card game popular among elementary school students—as he believes that it will save his home from a long war. With the siblings agreeing to teach Yudias about Rush Duel, they eventually realize that their first contact with an alien may not be a random coincidence. [Written by MAL Rewrite]

Born into a unique world where villages fight to gain power and control, the main character, Shi Hao, is a genius blessed by the heavens born under the poorest of conditions. His clan, however, has a mysterious past. To rise up and become the genius he is meant to be, the clan goes through every effort to aid his cultivation as they battle through fanatical monsters and engage in power struggles with other clans. His journey will bring him through unknown lands until he is able to become a person that can truly shake the world. (Source: Novels Xianxia&Xuanhuan Wiki)