Magic Forums

Everyone has a room in there mind that holds their deepest darkest fears in their mind, mine changes to who ever is present and I locked it away so it could't effect me. I also have secrets to hide from my self and intruders. I combined these two factors into one room, but there was a problem, the guardians I set got out of hand and started consuming the souls of the intruders and I didn't know this because I had it locked away so well. I nearly died energy wise along with a companion to guide me because I am blind to energy. When I got free I searched for a reason why it got aggressive to its maker. I found, what I describe as a black soul gem the size of a big computer desk.

I got rid of it properly and got ride of the room of secrets too, it was too dangerous. So here's my question: how could creatures who protect my secrets and use my special nightmare room tactics turn like this and nearly kill their creator. The 'programming' was simple and specific. any opinion?

Note: I don't intend to have any soul related damage ever happen.