Foxes are terrifying if you don't know what they are, and even if you do you can be caught off guard.
I grew up near fox cover, they'd come down from the wooded hills to scavenge/go after poultry.
We had a big dumb outside dog - one fox would go one end of the house making noise, which would send him barreling down to the fence barking like crazy. Then another fox would hop in and steal his food at the other end
Few spooky, not terrifying ,things have happened over the years.
In younger days, a large group of us went camping in a wooded area on the outskirts of rich people land.
Long story short as things fizzled out, 2 of us as we tended the fire, came to the realisation that there had been an extra person there the whole night, always standing just far enough away you couldn't see their face, at various edges of the clearing we were in where the vegetation got thick.
Next morning we started asking folk about it and everyone realised when they were talking that the person they thought was standing near them at a certain time had actually been elsewhere.
For a while afterwards we came up with all sorts of stupid teenager explanations of spooky origin but as we grew up we just kinda decided it was a local weirdo