I've updated the Open PK-ness of this event.

First of all, the ruins are still blanket Open PK.
Second, all rooms that have a banner from the three factions claiming it as territory are also Open PK (e.g. most rooms in the Aureliana, West Liruma around the Great Rock, and East Liruma around Mitrine).
Third, due to the above change, I've unflagged Aureliana as Open PK.
Fourth, attacking NPCs that are loyal to the faction (e.g. NPCs in their respective towns/headquarters) will mark you as Open PK. Not all NPCs are correctly marked with loyalty to their faction yet, so this part is rolling out over time.

Open PK in this instance means you'll gain the Hostility Aura as soon as you walk into one of the rooms, which will fade a little while after leaving the Open PK zones again. In the instance of NPC killing, this will last a bit longer than usual.

Each of the faction's headquarters are not open PK (though obviously attacking the NPCs in them will mark you as such!), and we'll be updating each of their areas with some stronger guards in the near future in order to make them a little bit safer for people to go in and get their missions.

Penned by my hand on Gosday, the 14th of Haernos, in the year 473 MA.