Мафия 59. Mystery of the haunted house

Playing dolls – the spirit possesses the body of a marksman if it's the only one left. It gains the ability to kill.

I don't understand how to interpret this.

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Does it mean it possesses the body of the brother?

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Is banishing Fabien equivalent to killing him?

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Or does it just cleanse the body of the spirit?

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And if we execute the Master of the house when he's possessed in someone's body, will the Master himself die, or the player that the Master possessed?

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Here are some questions for you.