Ages ago I got the Basius 2 kickerstarter and got two terrain stamp pads and I’ve finally got round to using it for some model bases. Writing this as a tutorial for anyone either using a similar terrain stamp or making their own.
I used modeling clay, which has a crumbly texture and worked well to simulate natural rock. Applying the stamp twice caused a faint trace of the first stamp with finer cracks on the surface.
Glue a blob of your clay/putty on the base, spread it roughly over the surface and apply the stamp. Take it off and using glue apply some sand/gravel to add some variety to surface (large then small). Leave to dry and after dry apply some watered down PVA to the sand/gravel to fix it in place.
Prime black and paint dark brown. Paint the top of the cracked earth a sand colour, adding some variety with a little dark red. I used an airbrush to do this quickly, but you could wet blend the colours in by hand.
Paint the larger gravel a light grey then apply washes to the rocks/sand/shaded areas using a mix of black and dark brown. Drybrush the cracked earth a mix of sand/white and the rocks grey/white, to leave a cold/warm contrast and give an edge highlight to the cracks.
Shade the cracks, which I did by an oil wash (applying a gloss varnish first to protect the surface). Apply a matt varnish to the base to make it look extra dry/dusty, and clean up the rim with a mix of black and gloss varnish to contrast with the matt base. Apply some extra flair like grass or skulls to add some extra points of interest.
This process can done on mass and you can change the colours to contract best with your models. A light/warm base contracts nicely with a dark/cold model, I used these with some models with a mainly green theme.