Board Thread:Bug Reports/@comment-27200931-20170213123546/@comment-27200931-20170217150915

SamwiseFilmore wrote: That's a pain. How far can the fire spread, on average? Most people aren't going to be building their base right at the edge of the protected zone, and most won't have a problem if the fire only spreads into their terrain a few blocks. Depending on the spread distance, it might also not affect naturally generated pyramids either.

I tested it and apparently Khâmul's Fire only destroys the blocks in the border of the protected area.