That module is a bit sucky, I was about to suggest it myself but it wouldn't destroy all buildings, just some random ones regardless of what seed number used.
Tried using a random seed number and running it several times in a row but then it would actually "fix" some buildings it destroyed earlier.. So it's a bit "BIS'd" as usual
It doesn't destroy all buildings into a pile of rubble because if the building has different destruction states it may "activate" one those instead so the large buildings that can have pieces blown off of them may only get one of those blown off.
Oh, and
["destroyCity",500,42,[]]
There is no need for the empty array there, it's optional so the function will only run through some extra hoops in vain if you add it there. Same with the seed value, it's also optional so you can add a value if you wish. Dunno what exactly it does, I guess it's some randomness thingy..