Sanity Rules!

Yes, it does. But not in the dungeon.

Keep this under your hat, as I don't want the rest of my gaming group knowing this: I have been using a rudimentary sanity rule in my Montporte Dungeon Campaign. Basically, there are certain circumstances where the players (and NPCs) are forced to make a saving throw and, if they fail, they lose a point of wisdom. Eventually, their wisdom points return and all is well. Unless the wisdom score drops below 3, then all bets are off. The player characters recently witnessed an NPC, Ansarkhan the mushroom man, go permanently insane. He is now in a catatonic state that is occasionally interrupted by quiet mumblings of gibberish.

I have used this simple sanity mechanic twice: In Session 1 and, more recently, in Session 24. In the first instance, there was no permanent damage done, but the second episode resulted in permanent insanity.

I like the idea of having a simple sanity mechanic in our current dungeon campaign, but I didn't want to spill the beans with the players or on my blog until I was able to use it to its full effect and the players learned that the victim (an NPC in this case) went insane.

I think adding sanity/insanity into the mix makes the dungeon a scarier place, but I think it only works when used sparingly. D20 rules do not really support a sanity-focused game and there are better rule systems if insanity is the focus. As an occasional threat, however, it could make the game more interesting.

I would like to fine-tune my sanity rule a bit but I am not sure if I should bother creating an actual house rule. I am also a bit undecided what it would look like. Here are a couple of options:
  • Wisdom + Charisma + Level = Sanity: I like bringing wisdom and/or charisma into the mix and also sort of modification for level. Under this scenario, characters would have a considerable amount of sanity and it would only slightly as characters progress (assuming a D20 rule system with level advancement).
  • (Wisdom + Charisma)/2 + Level = Sanity: This version takes an average of Wisdom and Charisma and then adds a bonus for level. Sanity is lower, but still influenced by both attributes. Level bonus has more influence, proportionally. I like this particular approach a lot, except that it looks like real math.
  • Wisdom Score + Charisma Modifier + Level = Sanity: My first reaction was "meh" but the more I look at it, the more I like it. Wisdom is the primary attribute here--being grounded, having deep insight, and common sense seems like it should be the buffer against insanity (playing fast and loose with the medical understanding of mental illness here). It is modified by "force of personality" (charisma) but charisma is not the primary determinant. After all, there are plenty of insane people with strong personalities.
  • Charisma Score + Wisdom Modifier + Level = Sanity: I really liked this, at first blush, as it makes charisma very important. However, I like the logic of having wisdom as the primary attribute.
There are a number of variations on these approaches but it seems a bit much to do an exhaustive list.

There are other ways that sanity scores could be modified: Race and Class come to mind. But that is a topic for another post.

I have read a number of blog posts on this, as well as various rule sets (I really like Crypts & Things). I am curious to know what you think.


  1. I believe I would choose the average of Cha & Wis + level. I'm not sure how C&T deals with it and this is like the third time this week someone has referenced the system for a rule. So I need to read it. And is there a rule for sanity in the Creeping Chaos book? I believe you have a copy of that also so that might give you a look at a d20 version of sanity rolls.

    1. I don't think there is a rule in Realms of Crawling Chaos but I could be wrong. I guess to look at it.

  2. I like the (in)sanity element. It does bring a certain atmosphere to the game. As for a codified house rule? I don't know. The rule you just used (losing WIS) seemed to work well. You could just as easily do INT or CHR or some combo. Maybe different creatures affect different stats (the black blob affects WIS, some other creature might affect INT, etc.) Then you wouldn't need an actual sanity stat (especially if the sanity effects are going to be used sparingly).

    1. I agree that I would just keeping doing what I have been doing. I would rethink it if I used sanity or taint in relationship to spell-casting, along the lines of Crypts & Things.