The rest of the crew were laughing now, the sound blending with the idle growl of the tank’s engine. The Mars-pattern chassis was grumbling where it stood a few paces away. Still in its factory grey, it did not look like a battle tank. Where the turret should have been was only a greased collar, and an opening into the chassis’s guts. Hull and sponson gun mounts were just empty slots. She could see the gunner girl Genji grinning out at her from where the forward hull weapon should be. Lachlan sat on the tank’s right sponson, Makis and Vail on the top of the hull, legs dangling into the machine’s open guts.

‘Inspecting the floor, Tah?’ The voice was high-pitched, almost boyish. Udo. It would be Udo. They all laughed some more. Terra, it was not even a good joke.

‘Just trying... to escape... your company.’

They laughed, and she breathed quietly.

The fall was her fault really. Udo could not drive to save his life, and the top of the gun mount had been a stupid place to sit for the ride. Even so she had to try very, very hard not to consider standing up and shooting Udo in the face. She pushed herself to her knees as a pathetic sip of air reached her lungs. She stood up, picked up her cap and jammed it back on her head. She was tall for a machine rider, but would have been short for an infantry officer. Wiry, warm-skinned and sharp-faced, she had a smile that she thought showed too many teeth, and her grey-and-greens always looked baggy, no matter their size.

She glanced away from the tank, as much to hide the fact that she had still not got her breath as to take the sight in. Behind the idling vehicle the chamber extended away, a vast rockcrete cavern lit by harsh light. Now that she was not riding on the tank she noticed how the sound of the engine had filled the space with echoes. The floor was a patina of oil stains and gouge marks from heavy tracks. A fine gritty layer of dust covered everything, and there was a cool, slightly musty smell, which betrayed that the ventilation system had not been active for some time. Somewhere above them, separated by layers of rock, plascrete and steel, was the Sapphire City, bustling with life while beneath it a warren of military shelters lay all but empty.

It was not actually empty, of course: two regiments and a few other stranded units lived in the upper sections. Then there were the stores, supplies for campaigns that had most likely ended long ago, all rusting and decaying in silence. Even in caverns like this one, there were crates stacked against the walls, and big blocky shapes under regulation green tarps. Despite that, an entire armoured regiment, perhaps two, could have vanished into the remaining space.