By destroy I guess you mean explode?
Well to explode the universe, would be impossible, as there isn't even nearly enough matter to ignite, or cause this 'fireball' type image. All that would happen is it would keep expanding, at light speed, same as it was before..

To completely destroy the universe, you'd need it to implode.., which is 'the big crush', the opposite of the big bang..

To do this you'd need to take all of the 100 billion stars, in all of the 200 billion observable galaxy's, times it by 100 (the estimated amount of dark matter present in these galaxy's) then times it by 10.
This is the approximate amount of matter needed for gravity to pull the universe back to it was before the big bang (if this is even possible)

View the original article here