Why am I so sure it's the city sniper? First, one shot, no mention of the attacker. It perfectly fits the profile of the same city sniper. Second, no giggling or deceptive tricks, which are how the GM usually indicates a werewolf's actions.

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Also, I have a theory why the Mafia keeps sending Envy. I think Pali isn't very active, and decisions about Night Kill are made without him or almost without him, so they decided to send him to take the blame. That wouldn't happen with Lynx: she's active enough.