[Extremely Disturbing]
A guy on YouTube orders a DarkWeb mystery box which was sold to him by a serial killer who kidnapped children. The YouTuber did go on the DarkWeb which is considered "play time" by many killers on the DarkWeb. The world's darkest individuals look at this place on the internet as their territory and in some ways, their Social Media space where they mingle amongst others who are into whatever they're into.
With that said, when a normal person goes into the DarkWeb, they can sometimes get caught by very sick people who think of it as an opportunity to play with them. They know where you live, where you work, where your kids play, where your kids go to school, BUT they have a code. They cannot harm you unless they warn you first and you persist to give them permission to play.
They warn you ONE TIME.
And they can do this by sending you flashdrives, letters in blood, hair, teeth, etc. This particular time was a bait attempt. When the YouTuber ordered the DarkWeb mystery box, the killer took that as a request to "PLAY." So the killer sent him murder clues and evidence... and then sent a warning.