Couple of ones I can think of...

I get sleep paralysis on occasion. For those that don't know, it's kind of when you get stuck in a state between REM sleep and being awake. You can't move, but you perceive the environment around you, in addition to "hallucinating"/dreaming in the environment. There is often also a sensation of having difficulty breathing.

Anyway, sometimes it's a bit scary and sometimes it's not too bad. But one time, I had an episode where a gigantic shadow demon climbed through the window in front of me and began slowly walking towards me all the while I lay there unmoving, straining everything I had to try to get up and get away to no avail. I thought I was going to die. But I woke up before it got me.

Another dream I had that messed me up didn't involve sleep paralysis and was actually very benign in comparison. I dreamt about my coworker's husband yelling at us. I woke up in the middle of the night and had a weirdly strong reaction to it. I straight up started crying which was totally unexpected for me. That's never happened for a dream. My father was an abusive husband growing up and I guess mentally it somehow put me back to way back then when I was a child. I have never had a dream that had me wake up crying before. I didn't tell my coworker about it, either. Her husband seems ok on a surface level but he gives me bad "vibes" and I am just all around not trusting of him. I care a lot about my coworker though.

Oooh ok I have one more but this one is funny. I had a dream where I had to amputate both of my legs with a power saw. This one was actually super casual and not scary at all...so much so that I found it hilarious to talk about the next morning with everyone. It was as casual as brushing my teeth in the morning. Not directly related to the OP since I didn't find it scary, but it certainly amused me!