Hydra Cordatus System

The Hydra Cordatus System is a forge-world star system on the Eye's doorstep in the Sentinel Sector, and one of the few vaults that stored Imperial Fists gene-seed. Hydra Cordatus itself holds the Cadmean Citadel; Hydra Minoris and Hydra-Xylen share the threatened well.

Perturabo cracked the citadel in the Heresy. A later Iron Warriors warband came back in Storm of Iron to finish the insult and loot what gene-seed still sat in the vaults. This is not Hydraphur, not a Pacificus fleet capital, and not a random Hydra-named rock. It is a Fists magazine on a bad border.

The Hydra Cordatus System still matters because some thefts do not get undone. Unofficial fan summaries keep the sentinel-sector parent and explicitly distinguish this well from hydraphur-system.