I Have a Manor in the Post-apocalyptic Era - Chapter 9 - Mental Energy Crystal

Known as the youngest academician-level senior engineer, Zhao Guoyang was reborn in the 1990s. In this era of economic globalization, with his extraordinary wisdom and extraordinary insights, he created one miracle after another and became a name that shocked the world!

Wisdom is condensed every bit, brilliance is created by sweat, and witness the rise of a great power!

- Description from novelbuddy

Reborn into the world of Yugioh, it's natural if my goal is to become the best duelist!

Once upon a time, the Devil fell in love with one of the King’s many wives. One night he went to her room disguised as her husband and made love to her. She got pregnant with his child. Knowing this The King ordered her execution believing his wife cheated on him, but then the Devil appeared to the king making him a deal. In exchange for great power for his Kingdom, the King will let his wife Sire The Devil’s Child. The King who was greedy for power agrees to the deal and his Kingdom becomes one of the most powerful Kingdoms and the Devil’s Child, the seventh Prince of the Kingdom.

Lin Yuan, carrying the “Door to Myriad Worlds,” transmigrated into the Great Universe of the Starry Sea.Here, the mightiest could obliterate star systems with the flick of a finger, and traverse millions of light-years in an instant.As a bottom-dweller, Lin Yuan could only rely on the “Door to Myriad Worlds” and his innate talent, “Against-Heaven’s Understanding,” to travel through countless worlds, silently growing stronger.【Your Against-Heaven’s Understanding allows you to cultivate the Muscle-Tenden Transformation Bible, comprehending the ‘Muscle-Tendon Transformation Blood Tempering Divine Technique’】【Your understanding is Heaven-Against, upon extending your comprehension to the Thunder in the Palm, results in the mastery of the ‘Thunder Creation Opening Technique’】【Your understanding is Heaven-Against, while observing the birth and death of worlds, leads to the insight of the ‘World in the Palm’】【Your understanding is Heaven-Against,, through studying the art of external incarnations, culminates in the ‘Self-Transformation Great Technique’】……In his unending travels, Lin Yuan ceaselessly grew stronger, until… he was unrivaled across all worlds.