Steam Fungus Leads Me to Rebuild Civilization on the Corpse of the Old God

This is a civilization built on corpses. The huge corpse of the ancient god stretches across the starry sky, and humans live on its fur like lice, digging into its bones to forge steel, extracting its body fat and burning the steam. Industrial black smoke obscures the sky, and acid rain corrodes the scars on the earth. In the sewers of the Undernest, which never sees sunlight all day long, a group of spores from another world quietly awaken in the sludge full of heavy metal toxins. It has no eyes, but can sense the tremors of all things; It has no arms and legs, but billions of hyphae can move huge gears. At first it was just a patch of mildew growing on an abandoned valve, fighting cockroaches for a few grams of rust. Later, it was the shadow that covered the entire mechanical maze, turning the steam pipes into its own blood vessels, and assimilating the difference engine into its own nerves. Faced with the purifying flames of the church, the steel legions of the plutocrats, and the indescribable things crawling out from the depths of the divine corpse... The voice whispers in the minds of all the parasites: "The flesh and blood are weak, but the machine ascends? No... Only mycelium connects all things." This is a story about devouring, evolving, and finally reconstructing an indescribable civilization on the corpse of the old god.