This Damned Thirst for Survival - Chapter 63

Of the ancient gods only one remained in the world. This god lived alone for thousands of years and no longer had any desires. Legend had it that during the great war between the worlds he used his powers to turn the tide managing to seal the cataclysmic rift bringing order back into the three realms. Time flew by and hundreds of years passed in the blink of an eye.

Zheng Tan somehow returns to the year 2003, turning into a black cat. Picked up from a rubbish heap by the Jiao family, he is given the name “Charcoal”, and so begins the life inside Professor Jiao’s family. Zheng Tan remembers that he was once a person, but currently his body is that of a cat. He has no way of speaking the human language, but can understand it, and even retains the thinking and IQ of a young 20 year old youth. Read along as he adapts to this new world, and somehow tumbles from a group brawl to catching a thief.

- Description from Novelupdates

The ordinary 18-year-old Edo, during a nighttime walk, finds himself in a fantasy world where he gains a mysterious power that could shape his destiny.

Senior high school student Dugu Hong was logical autistic and had a very high IQ. Despite his impressive IQ, he was never taken seriously by his teachers or schoolmates. While playing a recently released eastern Wuxia online game called Jiang Hu, three vicious classmates trapped Dugu into a mountain cave in the game with no hope of escape unless he deleted his account and re-register it. Not succumbing to their demands, Dugu decided to stay in the cave and explore the game system, which benefited him greatly. His persistence to obtain massive internal strength aided him in finding a superior way to improve himself, and thus opened the function of inner observation of the main and collateral channels. Meanwhile, in the real world, he discovered he had supernatural powers when he tried to save the girl he secretly loved who had caught the eye of a gangster on the suburban railway.