Crownless Reincarnation: New World? Nah I'd win - Chapter 13: Forest of Death [3].

A tree of 10,000 flowers, the world is the door.
The spells change a lot, but the hearts of the people are unchanged.

- Description from Uukanshu translation

An entomologist’s soul transmigrates into a cultivation world, inhabiting the body of a small, obscure cultivator who specializes in insect manipulation. Reborn, he desires only to avoid conflict and quietly develop in a mortal village.Inspired by the “Sun-Moon Heart Sutra,” he creates his own “Ten Absolute Scripture.” Inspired by the “Nine Deaths Divine Art,” he devises the “Purgatory True Demon Technique.” Moved by the “Eternal Life Sutra.” he extrapolates it into a hundred layers.With boundless creativity, extraordinary insight, and unlimited time, he pioneers new techniques, pill formulas, artifact designs, array formations, gu recipes, poison concoctions, and brewing methods—all entirely of his own invention.While others cultivate paths of slaughter, he alone forges and cultivates the path of self creation.

The world that nurtured the civilization which reached the pinnacle of magic was on the verge of destruction.
The last survivor transmigrated to the past, when the magic civilization started growing, as countless mages were still fumbling their ways through the thorny paths of magic knowledge.
He, who came from the end of the magic era, aim to reach the pinnacle of magic.

A story about a weak, small larva with a human soul, who travels all the way to become the ruler of the stars.