I'm in the process of painting a bunch of 28mm Terrapins for MA and am really pleased at how they are going.
I started to arrange what I'd painted onto a base with a few other scenic items (each base will hopefully be a mini diorama - that's the aim anyway). I was wondering if anyone knows of some sort of putty or basing material that you can 'spread on'. This way I can press the figures / terrain items into the basing material to create a more realistic looking scene.
I hope you guys understand what I mean. 
Cheers,
Ben.
EDIT: I know what it is now. Pumice stone. There is a company called Golden which do it. Great for filling bases and getting some good texture. All it needs is a drybrush (once dry) and some static grass.