As far as I can tell there are two things in ESO with the name of Agra Crun (translated as Blood Shield). Both are found in the Wrothgar DLC and are part of Orsimer lore yet despite sharing a name they are very different. One a literal shield, the other a shadow organization not unlike the Shadow Scales of Black marsh.

Now while the shield can be found in the House of Orsimer Glories with a snippit of lore for it, the organization has little to no info about it. All we know is what is told to us by Azrath a member of Agra Crun found at Faruun Stronghold. By his account Agra Crun is an organization of Orsimer that are raised since birth and designed to be the protectors of Malacaths faithful and do the direct bidding of Malacath.

Is there any other information we have on the Agra Crun organization? Were they named after the shield? Any major events they took part in? Are they mentioned at all in other games or did ZOS pull them out of thin air? Any new information or even some minor mentions in in-game books I have yet to read would be appreciated