Spread carnage and corruption!
Henzell says...
  1. (Spellcasting/2 + 2*avg school skill) * INT/10 * (1.5 ^ enhancer count). Spellpower has diminishing returns over 50: 'http://tinyurl.com/oeme7aj '- Stepdown formula is min(pow, 200, 50*log_2(1 + pow/50)). Capped at 200. Negative spell enhancers use 0.5, not 0.66.
  2. ...and the significance of this? It's related to conjuration damage and self-enchantment duration, and controls the probability of a resistable spell succeeding in a less-simple fashion. And other appropriate things.
  3. Note that the power of some spells is capped, most notably conjurations. This is indicated by having a short bar on the second I screen. (the # represent power, btw)
  4. Prior to 0.26, displayed as bars using # on a non-linear scale. Each # meant you had at least: 0, 10, 15, 25, 35, 50, 75, 100, 150, 200.
  5. A Ruby script (slightly incorrect) for calculating spellpower: 'http://pastebin.com/f114699d1 '. Another Ruby script (slightly incorrect) for calculating enchantment success vs monster MR: 'http://pastebin.com/f70a79d8e'

Information based on master branch and the great LearnDB.
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