We Killed the Alien Bull. Then Its Corpse Blocked Our Escape. | Military Sci-Fi Infantry Story for Sleep

Description:

On Salt Vault Seven, flooded extraction galleries run beneath two kilometers of unstable ice, while the Grind grows through the walls and attacks anything that disturbs it. A submersible crew is transporting an untrained recruit to processing platform P-7 and diverts through an older gallery when vein-crust seals the primary route.

The Grind senses vibration, sends armored Bulls through the ice, and uses a Maw to broadcast the voices of dead and living soldiers over the hardline. As the crew races for a pump gallery, the recruit is ordered to hold a pressure lock with a rifle he has barely been taught to fire.

This is "Cargo Does Not Ask" by Sascha Schmidt.