Board Thread:Episode Discussion/@comment-24993958-20170114144645/@comment-4010415-20170114223830

Either way, Crocea Mors is most likely not a Relic. The four Huntsman academies were built with one of their purposes being to lock away and protect a Relic - one for each kingdom.

Why, then, would one of those Relics be allowed to continue to be in the possession of the Arc family?

It wouldn't.

All four Relics were hidden away in each of the Huntsman academies.