When they Cry (Higurashi no Naku Koro ni) has a very intriguing crime weapon at the center of its mystery: a weaponized virus / biological weapon.
As a biological weapon, it causes death but under a most unusual manner: the victim believes that worms are crawling under their skin around their throat, so all victims claw at their own throat until they die. Other symptoms include paranoia, distrust, high levels of stress, and outbursts of violence.
Without giving away the "whodunit", it suffices to say that the villain takes advantage of the symptoms to accomplish the villain's goals.
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A virus that affects the brain, and causes a predictable change of behavior makes for a most interesting "murder weapon". With some careful planning, the villain is able to have some cause-and-effect, the paranoia / violent outbursts of the villain's victims was used to make the villain's conspiracy deeper and more mysterious.
Its not like the villain can read minds: but knowing that a victim will slowly grow more paranoid and violent as time goes on is sufficient for the masterminded plan to be carried out.
As such, it was insufficient to solve "the murder" of the story. To find the mastermind, you had to understand the meta-weapon. Yes, X killed Y in the local landfill, but X wasn't the mastermind... just another victim to the paranoia that the mastermind infected upon X.
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An unusual crime weapon is most needed for a mystery. By making something unusual, it provides a dramatic promise to the reader that the story is worth following.
As a biological weapon, it causes death but under a most unusual manner: the victim believes that worms are crawling under their skin around their throat, so all victims claw at their own throat until they die. Other symptoms include paranoia, distrust, high levels of stress, and outbursts of violence.
Without giving away the "whodunit", it suffices to say that the villain takes advantage of the symptoms to accomplish the villain's goals.
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A virus that affects the brain, and causes a predictable change of behavior makes for a most interesting "murder weapon". With some careful planning, the villain is able to have some cause-and-effect, the paranoia / violent outbursts of the villain's victims was used to make the villain's conspiracy deeper and more mysterious.
Its not like the villain can read minds: but knowing that a victim will slowly grow more paranoid and violent as time goes on is sufficient for the masterminded plan to be carried out.
As such, it was insufficient to solve "the murder" of the story. To find the mastermind, you had to understand the meta-weapon. Yes, X killed Y in the local landfill, but X wasn't the mastermind... just another victim to the paranoia that the mastermind infected upon X.
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An unusual crime weapon is most needed for a mystery. By making something unusual, it provides a dramatic promise to the reader that the story is worth following.