The silent Serpent in the muddy Creek

"I was walking down this muddy trail behind my middle school, though in the dream I knew it was supposed to be my current backyard. The grass was up to my waist. Down by the bend there's this slow, brown creek, and I felt this intense, heavy urge that I *had* to cross it to get my car keys, even though I don't remember losing them. When I stepped in, the water was freezing cold. Suddenly the mud under my feet started shifting, but it wasn't mud. There were dozens of thick, black snakes coiled together in the shallow water, just silently moving around my ankles. I froze completely. One of them, bigger than the rest, raised its head right near my knees and just stared at me. It didn't rattle or hiss or anything, which made it ten times worse. I tried to scream for help, but my voice felt completely thick and muffled, like I was shouting through underwater glass, and then I snapped awake sweating."