Hey guys, I'd like to show you how i do my Cracked earth style bases that are on all my Skorne. Now I didn't come up with this, i've seen it before but it was long ago and i'm sure the technique has been around even longer than that.
Personally when making a crack style base i use Green Stuff, a readily availible modeling putty. The putty comes in two parts: Yellow, and blue. When working with green stuff mix equal parts of both colors. and wet the tools your using so it won't stick to the green stuff.(this can be done by dipping your knife in the painting water)
When the Bases are dry you can drill though the green stuff and plastic base and it will be very stable allowing you to pin your figures to it.
Step 1: Find a picture of cracked earth as a refrence. Get some Green Stuff(the amount in the pic is WAY more than what is nessecary) and your bases.
Step 2: Take a small ball of Green Stuff and smear it out into the recessed region of your bases. You don't need alot for this and you only want to bring the base up to even with the edge. Once you have the GS smeared even, wet your finger tips and run it over the Green stuff to get rid of your finger prints.
Step 3: Allow the green stuff to cure for about 10-15 minutes. Then grab your handy dandy sculpting tool, I used an exacto blade. Wet the tool and then while refrencing the picture do your best to mimic the effect. I found small triangles worked the best. When you draw the lines make a few lines thicker, a few thinner.
Step 4: When completely dry spray the bases flat white and then apply a heavy Devlan mud wash(or your color of mud wash) and when that dries a heavy coat of Gryphone sephia(or sephia wash). Paint the edges black and your good to go! I dont have a pic of a single base but heres a pic of my Skorne using this technique.
Let me know if this helped you at all and enjoy!
P.s. There are other methods for making a crackled surface on your bases, some involve paint some, plastic card. I found this method super easy, with great results, it uses way less GS than you think, and you can scratch hidden pictures into when its drying.