The Mythos is a horrible and dreadful
knowledge to bear. Every time a cultist uses her knowledge of the
Mythos she will lose some of her sanity. If she continues to use
her knowledge she will finally go insane. Being insane will
result in many nasty drawbacks.
A cultist can restore her sanity by not using her knowledge of
the Mythos for a while or by going into trance.
When a cultist is disrespectful to the great Cthulhu she can be
punshied with a Sanity curse. Sanity Curses are removed when the
cultist makes a good sacrifice in a ceremony or donates a
sufficient amount of money to Master Chthughan.