I know he wasn’t technically in the game, but I really miss the on-edge feeling of Herobrine possibly lurking around any corner of my world, waiting for the perfect opportunity to strike. My fear brought me to deleting my first ever PC world in 2015 when I started having pumpkins mysteriously appear on the roof of my house; random wood blocks from my roof disappearing, and the front door opening without explanation: The pumpkins can be explained by Endermen, but I do admit that it’s strange that it kept happening every night; but the door part… that was just plain creepy, because not only did I make sure that I didn’t leave it open, but I actually heard the door-opening sound effect once or twice on a couple of nights when I hopped into my bed… no mob in the game can open doors (Zombies can break doors in hard mode, but not open them; I wasn’t playing on hard.
I know Herobrine never existed, but that part I’ve truly never understood. It was on the world seed 426 on version 1.8.1. The reason I know the seed is because I found a screenshot of the world select screen years later, and in it was a world named ‘426’; which reminded me that the world was named after the seed.