The Yunnanozoon was one of the most significant finds in the entire Chengjiang Biota. Countless papers and research documents had established its role as the transitional link between invertebrates and vertebrates — the ancestral form from which all fish, amphibians, and mammals descended. Humanity included.

The New York Times had once published a memorable line about the discovery: “If the Yunnanozoon had died young, the central nervous system of animals would never have developed, and the Earth would remain as forever lonely and silent as the distant moon.”

Now a catastrophe had brought the end of the world. At this inflection point in history, what was unfolding might be the sixth mass extinction — or it might be another explosion of life.

Extinction. Explosion.

Hard to judge in the short term. Impossible for Shen Cong to call with certainty.

It felt like an explosion — the Cambrian Explosion was the precedent, and evolved beasts were proliferating in exactly that kind of eruption. But it felt like extinction too — the fifth mass extinction, the one that ended the dinosaurs, had been caused by an asteroid impact; a meteor shower had now knocked humanity off its throne in the same fashion.

Either way, he hoped for explosion. Nobody wanted to be extinct.

He hoped, more specifically, to become the Yunnanozoon himself. The founder of a new era. The ancestor of a future civilization.

Even if he didn’t currently have a girlfriend.

“If the Lv1 era truly represents a transition toward metallic form, then Lv0 could be defined as the ‘Lv0 — Gradual Transformation Phase,’ and Lv1 as the ‘Lv1 — Invasion Phase.’ The Activity core undergoes metallic transformation, then begins invading surrounding body tissue. And then — would Lv2 be the ‘Lv2 — Metal Phase’?”

He opened the Apocalypse Journal and typed out his reasoning: Could metallic transformation be a phenomenon analogous to the ‘phosphatization events’?

Near the boundary between the Precambrian and Cambrian, Earth had experienced two waves of life’s explosion — corresponding precisely to two phosphatization events, periods during which phosphate minerals formed and accumulated in the oceans.

Phosphorus was a critical element for life and ecological systems — a key regulator of nutrient cycling, including carbon, across the Earth’s surface, and the controlling element of biochemical processes. Biological skeletons contained enormous quantities of phosphorus, and phosphorus had played a decisive role in the development of skeletal structures. The emergence of skeletons had, in turn, provided an enormous evolutionary advantage.

Two phosphatization events. Two explosions of life. The connection was not coincidence.

What the ancient organisms of the Cambrian had done with phosphorus — gradually acquiring it, and beginning to build skeletons — the organisms of the present were doing with Activity. Gradually acquiring it. Slowly undergoing metallic transformation.

Naturally, Shen Cong’s mind completed the analogy: the current global environment was an Activity accumulation event — Activity depositing itself as a resource throughout the biosphere. All living things drawing on it. Remaking themselves with it.

He shook his head and kept writing.

Mutants fit the metallic transformation model cleanly. But iron people — how are they explained? What does the Lv1 era look like for an iron person? I don’t have an Activity core. How would metal invade my body tissue? What is the actual relationship between me and Great Vajra?

Mutant reproduction produces offspring like Xiao Li Du — stronger Talent, higher ceiling. If iron people reproduce, would their children be iron people? And if so — what would the bonded vehicle be?

Or — are iron people actually a dead-end branch? Not the Yunnanozoon, but one of the unnamed, unclassifiable creatures fossilized beside it — present at the moment, but not the lineage that mattered?

Questions without answers, all of them.

If he collected every question like this from the Apocalypse Journal, he’d nearly have enough for a full volume of One Hundred Thousand Whys. Understanding any of it would require countless people working across vast spans of time.

The laboratory speakers were playing something upbeat.

“I love your face, I love your eyes, I love your smile that brightens every day…”

The cheerful sound pushed back some of the heaviness that the Lv1 discoveries had settled over the room.

Shen Cong set aside the larger questions and turned to more immediate work: a closer examination of the flesh undergoing metallic transformation — the flesh invaded by the Activity core. He had a name for it now.

Flesh-gold. The counterpart to bone-gold.

He prepared a sample for the optical microscope. The Research Institute’s scientists had included a usage manual; he followed it, failed several times, and eventually got a clean observation. He compared the flesh-gold sample against a sample of ordinary Pearl Mussel tissue taken from one of the non-Lv1 mussels he’d butchered earlier.

His conclusion: there seemed to be a difference, but he couldn’t precisely articulate what it was.

The optical microscope’s effective magnification was 1500x. At that scale, both samples looked like fields of round cells packed together, all showing a faint yellowish tint. Pearl Mussel or Old Pearl Mussel — they looked the same.

“The metallic invasion probably hasn’t progressed far enough to be visible at this resolution. Keep the Old Pearl Mussel alive for a few more days and document the next stage.”

Morphological study of flesh-gold: temporarily concluded.

He moved to Activity injection tests. The results were more interesting.

Bone-gold — conventional Activity cores — couldn’t be deformed; attempting to smelt them destroyed their stable structure. Flesh-gold, injected with Activity, retained full softness. And it showed exceptionally high tensile strength alongside that softness.

An ordinary knife couldn’t cut through it.

“If the metallic invasion continues to spread while maintaining that softness — the applications would be enormous. The question is whether fully invaded flesh-gold can still hold its flexibility. Or does it eventually harden?”

Soft metal.

He stayed in the lab until eleven at night, then called it done.

Late supper: large quantities of Activity fruit and Activity Pearls, finished with a measure of Bee Treasure. Before bed, he measured his height.

187cm. Up from 185cm. Still growing.

The extra height genuinely changed things. The wider field of view alone was noticeable.

He washed up and lay down.

Sleep didn’t come.

His mind kept circling back to the Lv1 era — the Activity core’s invasion of surrounding tissue, what it would mean to become a metallic organism. What you would eat. How you would process waste. How the brain would change, how thought would work, how growth and reproduction would function.

Stop. Think about tomorrow instead. Figure out how to find the meteorite fragment. You can’t excavate a whole drained barrier lake at random, and you still don’t know what a meteorite fragment looks like, how deep it’s buried, or whether one even exists here.

The meteorite fragment had become an obsession. A fixation that was edging toward something that would interfere with everything else. He knew it. Every day without finding it was a day he couldn’t fully settle.

He got out of bed, found paper and a pen, and started sketching approaches.

Activity is a form of radiation. A meteorite fragment probably carries that radiation — is the source of it. So — could I use Activity radiation to establish a connection with the fragment? Some kind of resonance?

(End of Chapter 211)