So it's in the tile image file itself? Forgive me for being dense because I have no experience with editing terrain images. The reason I'm asking has to do with allowing burrowing on tilesets in the TX. It looks stupid for subterranean units to burrow through roads and concrete, but if that is disallowed, it will impact heavily on the usefulness of those units on maps that are very urbanized. I'm attaching Crater=yes and ForceBigCraters=yes to the DIG animation, which looks more logical - but only if the smudges actually get drawn :/ If this can be addressed then not only would burrowing units look decent digging anywhere on a map, but there'd also be the added feature for the TX of craters appearing on those pristine Washington DC lawns
