MTL - Self-cultivation of Male Supporting Role - Chapter 4 gentlemen

A man is reborn into the world of Avatar: The Last Air Bender as a waterbender from Katara's tribe. Best of all, he was the same age as her, and he had a system with him to help.He knows the future and a system that lets him continuously get stronger by completing quests or long-term missions, as well as giving him the ability to copy abilities from others for himself. He will become invincible in the world of Avatar, even more so than the Avatar himself.

Ye Zichen was just a normal university student. Or so he thought.

During his patrol, Ji Xiu Yun, a marshal of the Empire, was ambushed and went missing. When he returned, there was a pure white creature crouching on his army cap.

Through genetic testing, it was determined that this cute and delicate little fellow was a creature that had faded away with the mother planet of humans 2000 years ago——a cat.

The last cat in the universe!

The people of the Empire were frenzied!

- Description from Novelupdates

Luis Hartmann activated the mysterious Portal and began the journey of traveling between two worlds. In Immortal world, there are various immortal cultivators who can destroy mountains and live for thousands of years. In his own world, it is a Western fantasy realm where people can become knights or wizards, with different kinds of races. Luis, using the resources of both worlds, rises through the ranks. The life seed that knights awaken when becoming apprentice knights transforms into spiritual roots in the immortal world. With strategic wisdom, he helped his family become the eternal family, dominating both worlds. [Knight + Martial Arts + Immortal Cultivators + Family building]