D.E.M.O.N.S: Getting Summoned Weekly isn't so Bad - Chapter 1861 Random Perspectives GO!

Nine Realms Sword Emperor, a legend returns, leveling everything.Genius monsters, trampled underfoot, powerful beings, wiped out with a wave of a hand.If people do not offend me, I will not offend them; if people do offend me, annihilate their entire family.

Li Yi accidentally obtained a black science and technology library, which contains countless books of the inheritance of high-tech civilization and records countless knowledge.

There are thousands of bells in the book, there is a golden house in the book, there are many horses in the book, and there are Yan Ruyu in the book.

Li Yi has completely turned into a bookworm, learning all kinds of knowledge from the library, grand unified theory, particle Tebo theory, …, acquiring various black technologies, superconducting materials, super batteries, intelligent algorithms, … .

- Description from novelbuddy

An alien race invaded the Earth on June 6, 2128. At the midst of this war, many nations allied with the alien threat and the war nearly wiped out the rebelling humans of the planet. At the edge of mankind's survival, the United Nations Army launched its forces to eliminate the immediate stellar threats that loomed over Earth.

General Seeker Carlean, commander and leader of the mission, risked and gave his life to destroy the immediate stellar threat. The battle was won though Earth lay in ruins. Perhaps mankind will live to see a few years of peace before the alien threat returns to wipe out their existence.

At the immediate aftermath of the stellar battle, the fallen Seeker Carlean awakens and finds himself at aged 17, living the peaceful life he lived 16 years before he died.

So begins a new game in the battle for humanity's survival.