I have Immortality In The Cultivation World - Chapter 546 - 306 Warning the Monkey by Killing the Chicken

Ernest Quelt, the alchemist renowned for his unparalleled mastery of alchemy, has perished.But his death wasn't a noble sacrifice in battle, nor the result of a failed expedition—it was a betrayal. The very comrades he trusted most turned on him, driven by envy of his growing power.Yet fate wasn’t entirely cruel. With his final breath, Ernest's gaze fell upon the tube that contained his greatest achievement: a perfect artificial being known as the Homunculus.More than just a vessel resembling a human, this creation harbored the power of a catastrophic beast—one that had once nearly brought the world to ruin.

Zhang Yuan, who has been reborn in a chaotic world, awakens the Divine Nest system in times of crisis.[Activate the Black Giant Ant, grant tenfold, hundredfold... unlimited strength][Activate the Jade Mantis, grant Basic, Advanced... Saber Technique Mastery][Activate the Nine-winged Celestial Cicada...]

30-year-old Jo Minjoon has always wanted to become a chef. He started his culinary career late in life, however, and is currently chopping onions at a restaurant. Regretting his life choices, he wishes he could go back to change it all and falls asleep. Meanwhile, someone out there is willing to give him another chance and send him back in time. How will he use the new powers he obtained from this mysterious being?

The world is terrorized by the powerful Black Witch who has been sealed in the moon. Every ten years, the night of Hexennacht arrives and a chosen witch must battle the Black Witch in hopes of finally defeating her.

As the current decade’s Hexennacht approaches, a mysterious girl named Kagami Kagami arrives and meets Horinouchi Mitsuru, the daughter of the previous Hexennacht representative.

It takes place between Kyoukai Senjou no Horizon and the City Series, two other series by the author.