Terrain deformation, y-axis terrain, physics objects, etc?

I have some general questions I need help with.

First, I need a asset that can destroy holes in terrain. As in, a tnt goes off, blowing a massive hole in the ground, also destroying the supports of a house that falls over.

Second, physics. Can I make objects that break apart? Like maybe a house blows apart when tnt is ignited inside?

Third, can I change the shape of the terrain? Also, is there any way that the terrain can have maybe 10 feet of ground, then open to nothing?

  1. Relief Terrain Pack v3.3 | Terrain | Unity Asset Store
  2. Yes
  3. use SetHeight, Mathf.PerlinNoise, etc.

Your techniques for #2 will be based on your game style. All of these are simplified in a voxel-esque system.