As the millennia passed, the easy energy of the volcanic vents began to stabilize, forcing a secondary wave of evolution. The Gorgon-Walkers were no longer the only titans in the ash. From the rotting carcasses of the ancient world, the Scavenger-Titans emerged. These were the Marrow Harvesters, creatures designed specifically to crack the fossilized ribs of the fallen Brontosaurs to reach the mineral-rich essence within.
The competition for resources turned the silent world into a theater of war. The Gorgon-Walkers, once peaceful energy-siphons, were forced to develop offensive biological weaponry. Their calcified legs grew serrated edges, and their sensory pits evolved to detect the specific chemical signature of the Harvesters. The first recorded conflict of the era took place in the Shadow Basin, where a pack of Harvesters attempted to topple a lone Gorgon-Walker.
The battle lasted for three days. The Gorgon-Walker used its bioluminescent sac to overheat its own blood, spraying a jet of boiling, acidic ichor that melted the Harvesters' chitinous plates. This adaptation—the ability to weaponize internal thermal energy—marked a turning point in monster biology. It was the birth of the "Breath Attack," a trait that would haunt the legends of every species that followed.
The Marrow Harvesters, in turn, evolved thick, lead-lined carapaces to resist the radiation and heat. They became the heavy tanks of the Cinder Epoch, slow but unstoppable. The ecosystem was now a closed loop of destruction: the Gorgon-Walkers harvested the earth, the Harvesters harvested the old world, and eventually, the two would harvest each other. The very soil of the Earth began to change, enriched by the hyper-concentrated minerals found in the blood of these new gods.