Riddle #285

Question: I cannot be seen, cannot be felt,
Cannot be heard, cannot be smelt.
I lie behind stars and under hills,
And empty holes I fill.
I come first and follow after,
End life, kill laughter.

What am I?

Question: What tastes better than it smells?

Question: What goes in the water black and comes out red?

Question: What asks but never answers?

Question: To many, I am life's source. I am also its most valuable resource. I create and burn my own precious element, and my destruction will be my punishment. What am I?

Question: I have 6 faces and 21 eyes, but can't see a thing. What am I?