Keeper’s Korner - Running Masks of Nyarlathotep

I’ve run the legendary MASKS OF NYARLATHOTEP four times (and been in it twice!), but in a real sense, you only get one real shot at it.
It is the holy grail of horror, and in my opinion the best, most frightening, atmospheric, awesomely realized campaign for any game. I could sit and read it again, and again, and still find something new each time.
Here are some of the lessons I’ve learned from running the campaign.
SPOILERS OBVIOUSLY FOLLOW.