So this bug instantly kills you and is very easy to do with the stairs or pretty much anything else in the game that acts as a stair-like thing, (ex. Slabs, going up blocks). Right now I will be explain the stair part: if you stand on the bottom half of the stair and roll up but then enter a building at the same time then you will instantly die. My video demonstration: https://youtu.be/b9XYncYvHZI