The Chaos Acheron-class Heavy Cruiser is an unusual starship in many ways. It was originally designed by the Imperial Navy to serve as a test bed for a new series of weapons based on the analysis of ancient -- and possibly xenos -- weaponry designs uncovered by the Adeptus Mechanicus in Sector 51, also the home of the ill-fated Portis Cthulhus. Whether the vessel's subsequent defection to the service of Chaos during the Gothic War is related to this unconventional origin is still debated by Imperial naval scholars.
The project was evidently a success, producing a starship with a formidable array of long-ranged weapons batteries and even longer-ranged Lances that would ultimately become the basis for the design of the Overlord-class Battlecruiser. No longer needing a test subject, only one Acheron-class cruiser, the unnamed BF/67-A was ever built by the Imperium. Unfortunately, the powerful vessel eventually fell to Chaos during the Gothic War and finally earned its name, dubbed the Chaos Eternus by Imperial Admiral Grove.
Notable Acheron-class Heavy Cruisers
- Chaos Eternus - Originally unnamed and only designated BF/67-A, the solitary Acheron turned to Chaos during the Gothic War. It would earn its name after escaping Imperial forces for the fourth time under Admiral Grove during the Scharnhorst Conflict.
Previous Acheron-class Designation
An Acheron-class Cruiser type vessel existed at the time of the Great Crusade and Horus Heresy. At least one of this vessel type existed in the fleet of the XII Legion, transporting the World Eaters' 17th Company commanded by Captain Argus Brond. It was destroyed in orbit over Terra during the Battle of Terra. It is not known if this class of cruiser was very similar to the future Acheron or the Cardinal-class Heavy Cruisers that preceded it.
- Battlefleet Gothic Rulebook
- Battlefleet Gothic Resources: Ships of the Gothic Sector, pg. 122
- Khârn: Eater of Worlds (Novel) by Anthony Reynolds