Frostgrave is cool, and the system is very dynamic and malleable, so my friends and me want to add some Chulhu mythos monsters and a sanity system to include a more dark fealing to the game.
The idea is to include a new stat, the sanity points (wow so original

). When this points go down to 0 the miniature goes crazy and stay in the game like an uncontrolled "Creature" with a random aptitude, maybe flee, stay doing nothing just crying or start to attack the nearby miniature (as examples). Also, some cons to those magician whos sanity drop to 0 in one scenario is to gain disadvantages for the campaign like claustrophobia, aracnofobia, etc... with cool thematic effects.
How to lose this points is with some "attack spells", the encounter with some monster and changing the spells empower system to use sanity points instead life points... so a magician would lose sanity points for pushing his/her mind to cast succesfully the spells.
A monster example,
Deep one
Move 5
Fighting +2
Shoot +0
Armour 12
Will +0
Health 12
Sanity 10
Weapon: Any
The deep ones can move through water terrain without penalties. Also if its movement is completily on water, its speed is increase to 7.
The first time a miniature is at 6" or less of a Deep one roll will against 6. The mini lose so many sanity as the difference.
So any more ideas?