The Wandering of an Unstuck Stepbro: Multiverse Travel - Chapter 1: The beginning

Meet Sora and Shiro, a brother and sister who are loser shut-ins by normal standards. But these siblings don’t play by the rules of the “crappy game” that is average society. In the world of gaming, this genius pair reigns supreme, their invincible avatar so famous that it’s the stuff of urban legend. So when a young boy calling himself God summons the siblings to a fantastic alternate world where war is forbidden and all conflicts–even those involving national borders–are decided by the outcome of games, Sora and Shiro have pretty much hit the jackpot. But they soon learn that in this world, humanity, cornered and outnumbered by other species, survives within the confines of one city. Will Sora and Shiro, two failures at life, turn out to be the saviors of mankind? Let the games begin…

He is a young man without a spirit root. It is believed that this denies him the chance at cultivation. However, a mysterious lady imparts a Supreme Demon Classic to him and from then on, he starts his path of cultivation.
He undergoes a total transformation to emerge as the most fearsome and powerful fiendish demon in his era, that even immortals and fiends are fearful of him, and saints are at his beck and call.
Mastering the Supreme Demon Classic is the turning point in his life. He is able to unleash his immense and divine power from within, illuminating the entire universe!

- Description from Novelupdates

When human beings ventured into the Interstellar Age, they encountered the Ochs Civilization, and thus followed the first Interstellar War.

Lost territories continued to increase along with the skyrocketing casualties. Eventually, humans were forced back into the Solar System.

In the 58th year of the Federation, Lin Fan, a traverser from Earth, graduated from the Interstellar Military Academy and entered the Federation Fleet.

That then signalled the day of the humans’ counterattack!

From dominating the Milky Way to the entire Universe, mankind never stopped.

This is a story of a traverser leading mankind to rule the Universe!

WARNING: FL is scheming and evil.