The footage came from the nose camera of an iron person's armored car. Every armored car in the Eastern Theater Command had a dashcam of this kind fitted.

In a picture that wasn't especially clear, you could see enormous earthworms boring up out of the soil.

This mutated earthworm resembled the ordinary earthworm in shape: a purple-brown body running in ring after ring, with hard bristles growing along the surface. Its mouth was very large but had no teeth, and it could attack by spraying soil out of that mouth. Its jin core sat in the clitellum, in the forward half of its body.

The clitellum was that fairly conspicuous band of rings on an earthworm's body. On the mutant it flashed silver, sharply different in color from the rest of it, and easy enough to make out.

Only four giant earthworms appeared in the footage, savaging the armored car.

Because the earthworms could attack from beneath the surface, the armored car had no way at all to strike back, and the iron people didn't dare get out of it lightly. All they could do was withdraw fast.

And during the withdrawal, the camera happened to catch an earthworm considerably bigger than the giant earthworms.

This one glittered with a purple metallic sheen in the sunlight. It plainly had no eyes, and yet it kept its head turned toward the armored car the whole time — and then, finding its opening, its body came slamming down. Using its clitellum jin core as a hammer, it drove an enormous crater straight into the ground.

The picture shook and juddered violently. With superb skill the iron person driver dodged the strike and got clean away.

That was where the footage ended.

There were several other recordings besides, all much the same in substance. One recorded a fight: the convoy had fired Mushroom Arrows in an attempt to kill one, and had only wounded the giant earthworm's surface. Once wounded, the giant earthworm bored straight into the soil and didn't show itself again.

The giant earthworms weren't especially thick through, so the area…