Terrain

As obvious from the utility's purpose, it cannot edit terrain. However, you can create or modify terrain in the regular editor, then use the unpack command to unpack the map and replace the old terrain with the new one.

$ kw unpack mapname.w3x -l

This command, when used with the -l flag, will not unpack the entire map but will only handle the terrain. Later there will also be support for terrain modules so you can load map templates with a single command.