Kids dressed as SHADOWS for Halloween – their mother bought black morph suits for them then layered black clothes over those. She says, “This might be the easiest costume on earth. And from all of my costumes over the years, this one got the very best reaction”
Yeah, this requires a thin layer of fabric over the face, which is sure to dim their vision, especially at night, it’s dark they can’t see nor be seen very well by other running children, cars, whatever. But darkness safety aside, that is the best damn costume I have ever seen. They really, really look like shadows, no easily seen texture or definition. Which is also very unsafe, because those costumes will scare the hell out of somebody and they may react violently. If one of those kids staggered towards me… yeah, just might kick him in the face. Yeah, not worth your kids folks, lets keep it safe.
Do It And How 
Bad idea. These are NOT safe in the dark evenings.
Sadly though cute, I agree – they’re very NOT safe.
Yeah, this requires a thin layer of fabric over the face, which is sure to dim their vision, especially at night, it’s dark they can’t see nor be seen very well by other running children, cars, whatever. But darkness safety aside, that is the best damn costume I have ever seen. They really, really look like shadows, no easily seen texture or definition. Which is also very unsafe, because those costumes will scare the hell out of somebody and they may react violently. If one of those kids staggered towards me… yeah, just might kick him in the face. Yeah, not worth your kids folks, lets keep it safe.