DD wrote:Opened muzzles I say!

any angle will help
and a destroyed building ... how do we do those?

Well, doesn't seem like any tips are being given, but I guess I can always refer you to an old pic of mine to show you ONE aspect of destroyed buildings that might help.
Note how the debris cloud surrounds the area where the tail strikes the building, and how the shattered parts of the building that break off are done at a different angle then the part of the building that remains standing. Falling iin or outwards depending on where they are relative to the tailstrike.
The good thing about buildings is that they tend to be fairly simple figures in most drawings. Squares and rectangles essentially, with some detailing. And definitly when you start drawing a damaged building, or one in the process of being damaged, I'd recommend starting with just the rectangle, because its very easy to draw perspectives and angles on a simple rectangle. Then once you got the building breaking apart the way you want it too, you can add all the details to it, and diversify and spruce it up a bit.
Its how most art works really. Start with simple shapes and fill in the details.
Hopefully that helps a bit.