@Vou
Already been made, you were beaten to it by 2 days. =)

https://powdertoy.co.uk/Discussions/Thread/View.html?Thread=6263

The one there is smaller, but slightly less powerful.

It's not actually that effective, to be honest. I tried it on 'Glacier City', it just melted the buildings and the large patch of ice. It hardly even touched the little underground area.