Engineering My Way to the Throne (DUBBED)

Engineering nerd Isaac Litt transmigrates into an ancient dynasty as the mocked son of a concubine. At his coming-of-age ceremony, he chooses a barren mountain as his fief and marries three women shunned by others. Using modern science, he turns his unfavorable circumstances around and overcomes adversity. As his rivals scheme against him, Isaac rises from a scorned son to a powerful lord.