In Different World with Naruto System (WN) - Chapter 327: Choodama Rasenshuriken

Qin Ran just wanted to cultivate immortality, refine pills, and live a carefree life as an immortal world slacker. But a genius female disciple just had to get clingy, insisting that he take her as a disciple. Not only that, she was always making advances on him, thoroughly disrupting his peaceful slacker life…

[Decisive killing! Invincible! No Madonna plot! 】

When a thunderbolt tore through the night and a blood moon descended, the world changed from then on, all beasts evolved, vegetation grew wildly, and wisdom was opened.

In just one night, the whole world fell into bloody chaos. The powerless human beings couldn’t stop the mutated beasts and the plants that started the evolution of Ganoderma lucidum, and countless human beings became their meals.

However, the people with the tattoos were horrified to find that the tattoos on their body surface also revived, giving them incomparably powerful power.

Gu Changqing travels back to the eve of the world’s mutation three years after the world’s mutation.

In his previous life, he was reduced to a low-level laborer because he had no tattoos on his body. Now he has traveled back and survived the troubled times. The first thing he did was to invite the world’s top tattoo masters to engrave the world’s top ten demon tattoos: Rahu, Qilin, White Tiger, Black Dragon, Death, Shura, God, Skeleton, Great Sage, Nezha!

Because he knew that engraving tattoos after the changes in the world would not awaken them and become powerful combat forces.

- Description from novelbuddy

The world was once at war with 10 alternate worlds. This was known as the Concept War and our world won 60 years ago. All of this was concealed so no normal people are aware of this fact in the current time.

After the death of his grandfather, the high-school student Sayama Mikoto is suddenly summoned by the giant corporation IAI. He learns this world is headed for destruction due to the acceleration of the Minus Concepts. To prevent this, negotiations must be undertaken with the survivors of the other parallel worlds so their 10 concepts can be released.

And so Sayama is caught up in the final battle to clean up after the Concept War which left behind so much enmity.

“Obtaining the topmost degree of talent in sword arts in the world requires giving up 72 years of lifespan, which leaves you with only five more years of your life. At the same time, you will never be able to feel love, kinship, and friendship, and you’ll end up leading a lonely life until your death, unable to procreate, or to have any descendants.“From now onwards, everything related to happiness in the human world shall no longer be of your concern. Are you willing to accept this?”“Hahahaha, I’m already alone bereft of all support, my hopes dashed to pieces, shouldering only absolutely irreconcilable grudge and hatred, why would I disagree? Why would I not want it? I couldn’t ask for anything better!!”His sword sweeps across the Divine Continent for seven days and nights, moving 90,000 miles through the starry skies, unhindered.He slays saints and buddhas in Heaven, slaughters demons and devils in Hell, sweeping away all the grievances in his heart.