Well, I remember two of the nightmares that freaked me out the most when I was little and looking at them today, they're absolutely ridiculous:
1: (This one I remember pretty clearly) I was coloring a picture of a bag of Skittles in my grandma's basement, and I looked behind me to find a spider, (I'm a huge arachnophobe) but it wasn't a spider, it was a Mario squid with snakes for legs and a scorpion tail. I was so scared by it that I ran upstairs, only to end up in the backyard of the house I used to live in. Turns out, the spiders were everywhere. My mom and siblings all huddled around me while my dad scared the creatures off, but my baby brother apparently didn't see these things and was just swinging on the swingset when all the spiders formed together into a giant fruit-roll-up and ate him. I woke up screaming.
2: It was Christmas Day and we had all gone to my grandma's to celebrate, as usual. I had opened up one of my presents and inside was an ear cleaning hat with some sort of liquid inside…? Well anyway, I then had to use the bathroom but when I was done I decided to try it out, and instead of trying it out for some reason I just used the liquid as a mouthwash, only to realize that the "liquid" was actually a mixture of OLIVE OIL AND VINEGAR (Dun dun DUUUUNNNNN) which apparently would clog my throat and choke me to death if swallowed or used as mouthwash. And so I died. When I woke up it took me a moment to realize I wasn't in the afterlife…
Those two dreams terrified me for so long…