Sword Art Online - Vol 6 Chapter 15

Yun Bixue is in dire straits—

The day a mysterious darkness enshrouded the world. It was theorized that the earth’s magnetic field had been changed, the data that corresponded to it also changed. The previous academic knowledge had been overturned, and numerous things had to be re-explored.

The science that humanity was familiar with had been disrupted, including the genes of human beings. One of the largest disasters brought by the change was that 80% of humanity transformed into zombies. After years of struggling, a few lucky survivors would evolve and awaken a power inside themselves. Chu Han was never that lucky.

While holding on against the first wave, humans weren’t the only ones getting stronger. Soon, stage 1 zombies evolved into stage 2 then 3 and so on. 10 years after the mysterious meltdown, the world of man belonged to the zombies. Humanity was nearing the of the end of the eschatology.

One day, Chu Han consciousness came back ten years before the end of the world came. He was awakened by a loud noise in a dormitory in Minqiu University. With only 1 day to prepare before the meltdown begins, he slowly begins to realised that he had undergone a rebirth. A power was awaking inside of him now despite never appearing in the hellish future. It calls itself the meltdown system.

Despite losing the monstrous strength gained through years of harsh training, this system claims to trade kills for talents. This is a story of a collapsing world, a meltdown system, and Chu Han being on stage as he travels to save those he could not save before.

- Description from Novelupdates

After breaking up with his girlfriend, he accidentally acquired a genius system and rose from there against the heavens, becoming invincible..

- Description from Novelupdates