The story of the Green Steve is that a Minecraft Player claimed to have met it in a Desert Temple. This person said that it hit him, and he was teleported in to a room full of Bedrock filled with Ice Headed Creepers. He turned off Minecraft. He emailed a Video Game Developer who had worked on Minecraft and the Game Developer Emailed back that Notch had wanted to have that in the game, But it was never added. And that person was found trying to hack Minecraft, if he had hacked Minecraft, there would be a whole new update never planned to be added. And that could explain Herobrine and the other legendary myths.