Blood and souls for Makhleb!
Henzell says...
  1. Nagas, octopodes (both player and monster), ball pythons, anacondas, tentacles- both vanilla and eldritch flavours- and tentacled monstrosities get this as an extra attack. Holds the target in place.
  2. Players and monsters can only constrict things of the same size or smaller. Players have a 1/3 chance to not be constricted. Teleporting (including blink, etc) allows you to escape and break constriction. Constriction reduces player or monster EV by 10.
  3. The chance to escape for players is 45%, 75% and 100% (increasing with every escape attempt). Monster escape chance is escape_power/hold_power. escape_power is 5 * escape_attempts^2 + HD + 5. hold_power is [{bvc}: 80 + power/3] or [{wand of roots}: 50 + power/2] or [otherwise: 3 * attacker_XL_HD + 40]
  4. Using boomerangs of dispersal on the thing constricting you allows escape (for now). Also: polymorphing it; becoming larger than it; invoking sanctuary; moving it with tornado.
  5. Octopodes can constrict up to eight creatures, depending on what they are wielding; others can constrict only one.

Information based on master branch and the great LearnDB.
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