>>101392984
>>101392911
The way it was always explained to me was that you get a chance of taking no damage when shot on lower difficulties but due to a bug it applied to enemies too so lined up shots would have a chance of doing no damage, but I've heard about the damage multipliers too.
However neither is true. You do less damage on higher difficulties and enemies do more. Your bullets don't vanish either. Both got debunked years ago with testing and reviewing the game code itself but sometimes people still spout it unaware.