It's all in the cards!
Henzell says...
  1. Enhancer staves (fire, cold, air, earth, death) have (2*evoc + magic skill)/30 chance of getting random2(1.25*(magic skill + evoc/2)) extra damage that ignores AC (except earth), but checks the appropriate resistance.
  2. see {staff of poison}
  3. Magical staves cannot be enchanted by scrolls or other means.

Information based on master branch and the great LearnDB.
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