User blog:Mr. Bambu/D&D Homebrew Calc: Castle Busting

Premise
At our table, Big Money Gripp, a fairly powerful Demon, was sent to destroy the party. He did so literally and shattered a keep a party member had earned. I will be trying to calculate this.

Calc
I will base this on the "hub" keep of our party, Guardian Keep, which is 500x600 in footage and four stories tall, disregarding the towers. It is made from solid stone, with each story being some 15-20 feet tall. We'll average it at 17.5, so total volume should be, accounting for battlements and such (we'll say four feet), 26640000 ft^3, or 754360.79 m^3.

We'll say 70% hollowness- the walls are significantly more thick than a typical building. So the volume of stone would be 226308.24 m^3.

Low-end V. Frag, High-end pulv. 69 and 214 j/cc respectively.

Low-End: 1.562e13 Joules, 3.73 Kilotons of TNT, Small Town level+

High-End: 4.843e13 Joules, 11.58 Kilotons of TNT, Town level

Cool.

Tally
Gripp Destroys the Castle (Low-End): 3.73 Kilotons of TNT, Small Town level+

Gripp Destroys the Castle (High-End): 11.58 Kilotons of TNT, Town level