I just decided to create something but i don't know what exactly...
So, many people don't know this trick with a smoke granade, especially at the initial ranks. This can give you an easy round win if the enemies enter the B site.

I stand in the corner, aim at the antenna on the roof as shown in the picture, stand up and just throw smoke. he flies, hits the wall, bounces and jumps onto the curb ... it turns out that you can see the legs of those running through, but they don’t see you. But of course, those who knows about this trick may be ready for it.
And yes, you don't have to shoot in the legs, aim higher :)