My Power is Upgrading Everything (Rewrite) - Chapter 3 - 1st Quest

There was a Senior Brother and a Junior Sister. One of them was transmigrated to this world and had cheats while the other was the reincarnation of a Great Emperor.

Fifty years ago, the oxygen in the atmosphere changed, giving rise to a new form of air known as Spiritual Qi. Humans, plants, and animals alike suddenly awakened latent mutant genes and began evolving, gaining Superpowered Talents and Classes. Life took a new turn, and humanity had to adapt.Everything seemed to be going well until, fifty years later, a 16-year-old boy named Klaus awakened a terrifying Talent and Class. His awakening marked the beginning of a new era in human evolution.Unbeknownst to everyone, Klaus, who was shunned by society and dropped out of school to work for a better life for himself and his mother, was actually the last of the Nine Paragons—a being so powerful that even the heavens feared him.Watch as Klaus climbs the ladder of strength, pursuing absolute power with a single purpose: to protect and make his mother happy.

A young man, killed because of his sister's identity as a Psychic, was reborn into a parallel universe's version of himself and began a new life.The growth path of a true villain boss. In the past life, he was ordinary and powerless to resist, but in this life, he awaits the moment to turn the tables

Ruins stretched across the landscape in the apocalypse after the nuclear war.