I posted this on the official WoW priest forums but didn't get much of a reception.

http://us.battle.net/wow/en/forum/to...93108?page=1#6

This idea actually sprung from a dream I had last night/this morning. It seemed like something that could totally be incorporated in game and wouldn't be that hard to implement, but at the same time I'm not sure Blizzard would ever endorse something class-specific in a pre-patch event (due to all the other classes demanding "where's mine?!")

Basically, I was just chilling alt tabbed in the AH in Stormshield on my shadow priest. I looked away for a bit, then looked back to my screen and went "WOAH." My screen was turning all dark purple and red for a couple seconds. It looked like I was dying, or other people were dying. The NPCs in the AH were replaced with Faceless Ones, and I was getting Old God whispers in my chat. It went away after a moment.

Overall it seemed very similar to the spider cave in Gorgrond where you start to hallucinate

Seems like it would be a cool pre-Legion easter egg sort of thing for shadow priests, considering that we're going Insane in Legion and that's a pretty big change.