Spectacular World - Chapter 223: Rescue Mission

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

At 18, Alex Kain is whisked away to Eryndor, a game-like realm where he gains 'Skill Synthesis', a talent to fuse skills into godlike powers. Battling monsters and conquering dungeons, he builds a harem of strong women drawn to his might and charm. With the power to return to Earth bearing incredible resources, Alex faces a growing threat that endangers both worlds in this epic of adventure, romance, and ambition.

A person's perspective plays a vital role in developing one's personality. What happens when you realize the world you live in is the same as a Novel.

Zero Elea gets a Skill called Parallel Memory which allowed him to get the memory of his alternative self of a different universe.

He realizes that the world he lives in is similar to the novel he used to read in his alternative world. The world will face catastrophe in the future but there is no need to worry as there is a main character working hard to save the world.

And what about me? I am but a mob character.

In the wake of the Battle of Katze Plains, the banner of Ainz Ooal Gown flies proudly over the city of E-Rantel. The Sorcerous Kingdom has entered the world’s stage to the clamour of death and devastation; the surrounding nations fearfully prepare even as they reel from its calamitous debut. Within the borders of the newly annexed realm, its Human subjects cower in their homes as the Undead openly walk the streets and stalk the lands. Yet, when a destitute noble finds herself under the auspices of an unlikely benefactor, events are set into motion that will resound over the world for ages to come.A kingdom builder based on the events and setting of Kugane Maruyama’s Overlord. In a fantasy world where beings of matchless power are transmigrated from the arbitrary existence of a game, Valkyrie’s Shadow chronicles the lives of the natives whose reality has been turned upside down by their advent. It is the tale of a nation created by the whims of a supreme sovereign, and his unstoppable servants who each have their own, often twisted, interpretations of their Master’s Will. There is no victory in strength; no miracles wrought from magic that will save them: only the inexorable advance of a new world order where those who secure a place of service within will find themselves turned against the world that they once knew.[Slow buildup. Methodical storytelling with a focus on well-rounded kingdom building and character development.]