Мафия 6. The Will of Swamps

Please also note that the last newspaper is called something like "Look for my name..." - maybe this is an indication that the clue is simply given in the form of a nickname?

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The struggle between light and darkness is waged in your souls

Let's look at the emblem of the "Witches" clan in Lisa's signature - it seems to represent the opposition of light and darkness, right? The fact that Vistrit was lying "snow-white" is again an indication of the white color.