My partner and I foster cats, and most of them love it when we roll toys back and forth between each other for them to chase/intercept. One time we decided to use an "invisible toy" where we just brushed our knuckles against the carpet as if we were rolling/catching something, and our poor foster kitty freaked the fuck out and it took a good 10 minutes or so for him to get back to baseline after we realized we should stop. Never done that bit again 😅