Shen Cong spent the next three days in Gaoche Township without going anywhere, working through the materials he'd brought back.

Zhao Yang's ten notebooks.

Much of the content was beyond him — the technical level outstripped his education, and large sections simply didn't parse. But scattered throughout were passages in plain language, particularly the theoretical speculations on evolution, which Zhao Yang had written without heavy reliance on specialized vocabulary or English terminology.

The notebooks also documented his pharmaceutical development process in substantial detail.

For the terms Shen Cong couldn't follow, he substituted his own approximations and pressed on.

Zhao Yang and his research team held a unified view: the entire Activity absorption process — everything that constituted the Lv0 — Activity Era — was fundamentally an act of environmental preparation. Activity was remodeling organisms — humans, plants, animals — conditioning their bodies to tolerate what was coming next. The metallic contamination.

When the Lv1 — Pure Gold Era began, that contamination commenced in earnest.

The analogy Zhao Yang used was construction. Building a house required three phases: first you laid the foundation, then you built the structural walls and frame, then you furnished the interior. Metallic contamination followed the same logic. The Lv0 era was the foundation — remodeling the body's baseline constitution to make it suitable for what followed. The Lv1 era was the structural phase — bone, muscle, and epithelial tissue replaced by metal one layer at a time, the body's primary framework rebuilt in new material. After that came the interior — the metallic invasion of hormone systems, sensory tissue, and the organs governing the five senses. And finally, the wiring and plumbing: the nervous system.

A vivid analogy. And not without logic — at least the prediction for the Lv0 — Activity Era had matched observed reality.

From this framework, Zhao Yang had classified organisms' responses to Activity-driven change. Based on how bodily fluids responded, he divided outcomes into three categories: mutation, resistance, and no change.

No change meant the body simply didn't interact with Activity at all — no chemical response of any kind. Most…