dummytilerange <tilenum1> <tilenum2> <x-dimension> <y-dimension>
Used in Def files to create a range of blank tiles at from position <tilenum1> to <tilenum2> of the dimensions <x-dimension> and <y-dimension>. This allows the creation of placeholder tiles for use with definetexture without having to edit Art files.
Also see dummytile.