Quote:
Originally Posted by Zikke
Maybe the variance is part of the balance on the spell? Making it a bit unpredictable makes it a bit less uber.

It doesn't matter from a balance perspective. The spell has to be balanced based on the average damage it does, and 1d150 and 3d50 basically have the same mean (the latter is, yes, 1 point higher, but that's irrelevant.)
Note that 3d50 is still wildly swingy. The variance for NdS == N * (S^21)/12; the standard deviation is the square root. Given the size of S, we can basically drop the 1, and say the standard dev == (sqrt(N) * S) / sqrt(12) ). For 1d150, the standard deviation is simply 150/sqrt(12), or about 45. For 3d50, it's sqrt(3) *50 / sqrt(12) or 1.7 * 50 / 3.4...or about 25.
And note that this also means you're much less likely to get a really *good* roll. A good roll may well be more useful than a bad roll is damaging.
And IMO, the balance is fundamentally the fact that the damage is so low. Fine, it's hitting a boatload of critters...but you have to hit them over, and over, and over...or their natural healing will kick in to some degree.