What a lot of the victims remember is a sense of unreality, a feeling like they were watching a movie. K. says she opened the door of her Florida apartment one evening to find a dozen SWAT officers lined up on the stairs with riot shields and black guns pointed at her. She froze and thought of the metal belt buckle she happened to be clutching in her left hand. They’re going to think I have a weapon in my hand. They’re going to shoot me.

Obnoxious often sent a text to his target telling her that the SWAT team was on its way — too late to stop it — just so she would know it was him. Sometimes victims received phone calls from the police before the SWAT team arrived. A Canadian Twitch streamer named Maple Ong got a call one night in January 2014, telling her to leave her house with her hands up, along with her panicked father and younger brother, so the police could search it for bombs that Obnoxious had told them were placed there. Allison Henderson, a 26-year-old artist and streamer who lived with two other streamers in Costa Mesa, Calif., received a phone call one night from a woman with the Police Department, asking her how many people were in her apartment and what she was wearing. Allison and her roommates had recently been DDoSed and harassed by Obnoxious. The policewoman told Allison to step outside with her hands above her head.

‘‘I held my breath and slowly opened the door to the sight of rifles pointed at me from every direction,’’ she says. ‘‘It was the most terrifying experience of my life.’’ When officers questioned her, she couldn’t make them understand. ‘‘They were completely lost on the idea of a stranger harassing us over the Internet,’’ she says. ‘‘It’s a feeling like you’re drowning, and the person doesn’t understand what water is.’’

A few months after Obnoxious swatted Janet and her family, he swatted them again.