I remember it as being my first dream ever, think I was around 1-2 years old when I had it, but everything's very fuzzy timeline-wise up until I was around 5.

It was wholly abstract, I dreamt of myself as an amorphous mass of... something. I wasn't panicked that I had no limbs or defined shape, and was fully aware of myself as said mass.

I was floating in a void, and a much, much larger mass of the same something of which I was made started drawing nearer and nearer to me, almost painfully slow.

I can't begin to describe the sheer terror I felt when I realised I couldn't retreat fast enough to not get caught. I was... moving my ass off away from the thing, and it seemed to just be strolling its way closer and closer - the fact that it seemed entirely relaxed in its pursuit somehow made the feeling of terror even worse.

Then, it finally caught up with me. The first thing which struck me was its size. To say it was towering over me is an understatement, the thing was incomprehensibly vast.

It was all over in a flash. The thing just... advanced "through" me, it simply assimilated me into its mass and I was gone. That was when I woke up. I still remember that terror, never felt anything close to it since.

I had a nightmare that a video of me accidentally bumping into a woman and knocking her out of her wheelchair went viral, turning me into a social pariah. I lost my job, my family abandoned me and I got hounded by people everywhere I went. It was one of the few times I remembered a dream very vividly and was genuinely releived when I woke up and realised it wasn't real. Don't know where the hell that came from.

Not sure if it's the most messed up, but it's stayed with me for more than 30 years. I dreamt that my younger brother had fallen off a bridge into a river, and I was in the water, trying to save him. I was somehow able to stand with the water only just past my ankles, and was frantically sweeping it aside left and right with my hands, but I just couldn't find him, despite the shallow depth. Absolutely horrible feeling, and I can still see it clearly nowadays.

I was maybe 10? Or so at the time, and I had a dream where I was having fun playing with animals. I didn’t realize there was also a venomous snake there, too… it bit my leg and it hurt really bad. Then everything went black. I knew I was dead, and could still feel the pain and hear/feel things around but horrifyingly distorted. My family was crying but all I could feel was pain. I floated around until I woke up.

Maybe 12? I had a dream where I was decapitated. When the sword went through my neck, I could taste the blade’s metallic taste (or maybe it was my own blood? Wait no, the taste went away once the blade was through.) my vision stayed clear for a few seconds as I rolled away from my body… then everything went red, then black.

Bonus: this isn’t a dream, I think, but occasionally when I’m falling asleep, I get exploding head syndrome. But there’s ANOTHER thing that happens that’s similar, where my body sinks down into the bed, into dark black weightlessness. Every time this happens, a VERY LOUD wind sound starts blowing and my body gets thrown around like I’m in the middle of a tornado, but the tornado is just spinning randomly. Just whipped violently back and forth, then I wake up panting and sweating. Kinda tough to go back to sleep when it happens.

I was a big bee (or maybe a normal sized bee but I felt big, maybe all bees do) gathering nectar from big yellow blobs with a human baby in each. I say gathering nectar, but I'm not entirely sure what I was doing, when I woke up it made me feel more like one of the big mechanical spiders tending to the pods in the Matrix. Woke up and suddenly felt really strange but it was very mundane in my bee head, didn't feel like a nightmare. I can't remember having another dream where I was not human/humanoid or a floating consciousness/3rd person, but an entirely different kind of being.

Had tons of technically weirder dreams (like the one where I was chased through the jungle by an unrelenting murderous bag of crisps that was so old and moldy that it became sentient and whose whole purpose was to kill me, before eventually getting saved by space faring people that brought me to a beautiful ivory cliffside city), but this one felt particularly weird as a departure from the usual and familiar insanity of my dreams.

Probably the one where some strange artifact showed up and turned out to be highly radioactive, causing my skin to slough off.

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!

The one about the head of my sister.

It was a total tragedy. My sister dies at fifteen in a train accident, all messed up. Except her head. While mourning for her, my family members start hearing rumors about her being miraculous. The rumors became a cult. The thing is, my sister's head was invulnerable. Her head wasn't damaged at all in the train wreck, and even dead, her head wasn't decomposing.

People started coming to see it by themselves. It was true. Her head was pristine, but for us, for me, it was still my older sister. The cult became a part of the church. They built some temple for her head where people could go to see her. I remember the altar. It was all made of crystal, sometimes they put flowers there, giving it some color. Her head was inside a crystal cube on a pedestal, so people could watch her from every direction. They put her a crown, like a quinceañera (this is similar to a humble crown in one of those female beauty contests). To get to her head, people had to climb like a hundred crystal steps, curved, not straight.

My sister's head wasn't neither alive. The head didn't age but also wouldn't talk. Her eyes were always shut, but you could see her face, her mouth displaying different recognizable expressions, like a shy smile or some concern. She looked beautiful.

Hey, lay off some horror for now, dude.

Find something calming, I dunno, put fire-cracking video on loop from YouTube.

When I was around 6 I had this really vivid dream of me and my family trying to run away from a spider that was the size of a dumptruck. Eventually it started ending each of us by piercing through our abdomen.

Alternatively, there was a time when (was also about 6 when I had it) I dreamt I was getting run over slowly by a huge car. Everything about these dreams felt real- even the pain 🤣