Conundrum

[brizzer]

Can anyone solve this riddle please? I bring life but bring death; I crush but lighten; I am black as night but light as day. What am I!

[hammersgirl]

I would guess water, if I was desperate!

We need water to live, but it drowns us. A lot of it is heavy, but it can make things buoyant. A lake/the sea is dark, but rain /snow is transparent.

[brizzer]

Thank Hammersgir- we'd thought water, but it's not the answer that makes you think YES!