Death March kara Hajimaru Isekai Kyusoukyoku (WN) - Book 2 - 2-2. Let's Learn Life Magic!

What would you say is the most valuable thing in this world?

Lucia grew up not knowing she was a princess.

A supreme expert in the Immortal World had died, and a strand of his soul returned to its original body on Earth. Tang Xiu discovered with amazement that ten thousand years passed in the Immortal World, yet only a single year passed on Earth.

Bai Muchen had it all — not only was he the most renowned martial artist of the Nine Heaven continent, he even had the Five Meridians of Tianling and was engaged to Xuan Qingzhu, the beautiful daughter of his mentor. But everything falls apart when he’s set up by his fiancé and mentor during a cultivation session, and he is killed.

Reborn as a young man named Xiang Nan, the heir of a declining family, can Bai Muchen get his revenge?