The Salt-Choked Vault

A drowned arm of the Imperium's bronze-vault architecture half-taken by the sea — the Sundering cracked its processional hall open and the Mirrenmere poured in, but something in the deep still keeps warm.

Fluted columns stand in salt water up to the capitals; the workings guttered long ago except one, deep in the apse, which pulses slow and cold in the dark below the flood-line. The Listening College knows it exists and has never reached it. Vault-weepers patrol the saltwater nave, and drowned Imperium constructs keep their stations at the flood-gate.