So I was in the Enclave last night and somebody was sneaking around, metagaming the Guards. I have no clue who it was, but I heard the wards there cast Spell Breach on somebody, and then I saw several of the Golems move on their own as if they were being spoken to.
So I think that a new security measure that should be added to Guild Halls is that the spell "Faerie Fire" is automatically cast upon any who enter the Enclave or other such Guild Halls.f
And, in fact, being the Enclave, it would naturally be Red of course.
