Our club is looking to expand the amount of Difficult Terrain/Terrain Areas we use. So I'm looking for simple, easily storable options to consider. I know I've seen a post a little while back that was looking at Difficult Terrain Zones that were done in a similar way to playmats but I can't remember how the person got the zones themselves, does anyone remember what I'm talking about I'm having trouble finding it? But I also bet I am missing something obvious and there are probably other really good ideas for mapping out zones like this.
Muse On Minis sells sets of 2d hills, foliage, and water features. I think they're printed on mousepad material.
I picked up some foam sheets from the local craft store and cut them into random shapes. A few different colors allows for some variety in the terrain too. https://www.michaels.com/creatology...DqYiWNeJS_MCZnWlhA-K-Fe-mNsKLESRoC4yMQAvD_BwE
For natural zones, do what Duke suggested-- buy brown/grey/black craft foam, and sponge paint it to look like dirt, broken stone, etc. To whatever extent is possible, match the colours to your playmats. Urban/Artificial zones are trickier, because you usually need to justify the "difficulty" of the zone a bit more. Heavily cracked pavement is a decent way to do this, as are "rubble zones"-- basically, patches loosely covered in small (shorter than S1) crates, barrels, pallets, stray lumber, etc. You could also justify areas of non-continuous ground as a difficult terrain zone-- e.g., a large grating that people need to walk over more carefully. All of the above is doable with craft foam and foamcore. :)