The change of his status to Friendly is the part that doesn't make sense. It killed 20 dwarves while in were-form, then... Friendly.
A complicating factor is that this involves several different issues mangled together.
* Lore / philosophy / code of law questions... Is someone under the influence of a hostile transformation, like were-ness, "the same" person? Are the two (or more) states responsible for each other's actions? How berserk are the weres, and how much (if any) are the base person aware of what has happened? Are there moral differences between an original were, personally cursed by a god, and those they spread the condition to?
* Observation / dwarf state engine / rumor tracking / justice system / etc. questions: How do dwarves observe and keep track of transformation information? In various fiction, it's frequently not obvious that initial attacks are a were-creature (as opposed to a particularly vicious, large, and/or rabid "natural" creature); and even once a were is suspected or even proven, it is frequently not obvious who the "base" person is. Dwarven justice is not generally good at inferences from indirect observation. While the player with their overhead view and inspection tool may well be sure that tavern visitor #37 turns into a blood-soaked monster on the full moon, if no surviving dwarf has witnessed the transformation, Dwarven justice may not be good at assigning blame.
We probably need a dwarf justice system for accusing potential weres, like vampires.
* Underlying engine and rumor tracking issues. Especially with the systems currently being worked on, which try to balance between the fun of rumors possibly being false, and the practicality of pruning information trees for performance.
Will we ever get Dwarves playing what amounts to an in-simulation deadly game of
Werewolf? Not even the Toad can be sure.
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