I'm Trapped Inside a Prince as the Most Powerful Entity - Chapter 5: Glimpse of Adam Power

Cao Xin, a young man on earth, died in a car accident, traveled to a troubled world where supplies were scarce, and obtained a “Bronze Immortal Gate”…

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- Description from novelbuddy

The story is about a a hitman, Who dies because of his own recklessness and transmigrates into a game he used to play after his retirement as a hitman.I'm not gonna spoil any further, but i might answer few of your questions.Is MC overpowered?Nope, he'll become strong over time and all battle he'll fight will be because of his effort and techniques.Is there magic and adventure?Yes! It have both magic like normal isekai with adventure and fighting with monsters and many other things. There are other important things like “Essence Stone” But let's talk about it in the chapters.There will be harem?Not really, He will be in contact with many beautiful female and males but one waifu but i haven't decided yet.All i can say is, give it a try, I'll try my best to make it worth your time.

Song Cheng transmigrated and became a blind errand boy in a medicine shop in a remote town.Fortunately, after he found a wife who did not disdain him, his “Golden Finger” also followed.Demons and ghosts roamed the Chaotic World, Profound Techniques went with Occult Sciences, Divine Weapons dazzled the cosmos, the Yin and Yang were inexhaustible.Song Cheng did not seek to dominate as a king, he simply wished to live his life well....This is the story of a person with Longevity, who walked through long years and witnessed innumerable Dynasties.