Terror Infinity - Vol 12: Chapter 5-1.

A skilled but unfortunate modern-day assassin was killed in a freak accident. However, he soon found himself summoned to another world by an evil wizard, who had him possess the body of a boy as an experiment. After successfully planning the evil wizard’s downfall, he used the wizard’s body as a springboard to gain influence and power in his new world.

- Description from Novelupdates

Shao Di Yu, an orphan, is adopted as a result of of a murder case involving the deaths of his entire family. Because of some painful experiences, he refuses to speak. However, he has sharp insight; moreover, he becomes under the care of a pair of twin brothers in the police force, who also have a child currently in university. Yu Yin possesses yin-yang eyes, which allow him to see things ordinary people cannot. The two brothers happen to complement each other, and together they investigate various inconceivable incidents.

Throughout this current life of mine, I will pay no attention to my past lives, nor will I seek future lives. I wish to live vigorously, to pay back debt of gratitude and fulfill duty to avenge, to defeat valiant heroes from all species, and to proudly laugh at all the Gods and Demons of the Six Path of Reincarnation!

- Description from Novelupdates

[No weak protagonist, No simp, Prodigies battle for supremacy, Explosively satisfying invincible (Overpowered) protagonist type]Jun Xiaoyao transmigrates to a Xuanhuan (mysterious fantasy) world, becoming the Divine Scion of an Ancient Aristocratic Family. He possesses an unbeatable background, world-shocking talent, and furthermore, obtains a sign-in system. At the very start, he signs in and receives a fully developed (Great Accomplishment) Ancient Sacred Body.Signing in at the Taiyue Ancient Stele, he obtains a six-star reward: the Divine Elephant's Prison-Suppressing Strength!Signing in at his ten-year-old banquet, he obtains a seven-star reward: the Supreme Bone!Signing in at the Bronze Immortal Palace, he obtains an eight-star reward: the Myriad Creatures Mother Qi Cauldron!Signing in at the Boundless Realm Sea, he obtains a ten-star reward: the Great Art of Transforming into Freedom!Countless years later, Jun Xiaoyao sits cross-legged in the Ninth Heaven, points his sword towards the Azure Sky and declares: “Across the Nine Heavens and Ten Earths, I control destiny! At the end of the Immortal Path, I am the Apex!”Novel Keywords: Opening with a Sign-in to an Ancient Sacred Body