Vines. And some large plants. This is mostly from old B-movies about man eating plants. As a park ranger, I managed to overcome my fear, but I still have a healthy respect for vines and don't like turning my back on them.
There was an old movie where Christopher Lee plays a mysterious man on a railroad train who tells the futures of some of the passengers. One vignette involves a man returning home from a business trip to find his house is being taken over by man eating vines. The next day, I noticed a vine peeking up through my back deck. I figured I'd take care of it over the weekend. Within two days, it had completely covered the deck. Just like in the movie. I decided to use the front door for the rest of the summer. Fortunately, my landlord has no fears of plants, and he removed it.

This is the first time in my 59 years that I have used the word "Vignette". I must be getting cultured.