Falling Damage as a weapon.

If an object or creature were to fall from a height of say 20feet onto a creature. How damage would that creature take?


Would it take 2d6 like the object or creature falling if so does weight not factor in?

Say a troll fell of a cliff of 40 feet and there was a part he fell onto would they each take 4d6? Or would the 500 pound giant have more of an impact?

That's up to you. There's no rules as far as I'm aware for something falling onto something else and causing damage. It would depend on the material I suppose.

Remember, a key approach to 5E is that the DM should make Rulings, and not be limited by Rules.