Go forth and aid the weak!
Henzell says...
  1. A passive property of {poltergeist}s. Hostile monsters gaining non-poison debuffs in sight of you increases your AC for a short while, with extra AC for the first one debuffed and +1 AC for each further enemy debuffed. Initial AC gain and full AC caps both scale with XL.
  2. Beyond just Hexes, there's weapons of draining / chaos, Alchemy, Hep / Ru / Uskayaw, wands (including acid, light, and roots!), and scrolls of fear / vulnerability / immolation. Makhleb's Destruction, Kiku's Black Mark, and Xom's random whims all also can help.
  3. <Ge0ff> "You feel bolstered by spreading misfortune". hlp, it's about the 4th time i read this message as "by spreading misinformation" <not_that_greg> "Don't go into crypt without rN+++!" the player poltergeist yells to buff up before the big battle

Information based on master branch and the great LearnDB.
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