I started out with a bottle cap which was the size of a 25mm base. I then removed as much of the side ridges as I desired. Using the InstaMold, I copied the piece a few times to easily make a couple dozen copies.
After priming the bases, I painted the inside area of the bases with Chaos Black. I didn't worry about the outer area as I would most likely have to go over it again in the future anyways.
Next, I mixed green ink from Liquitex in a bottle cap with some Turquoise paint. As you can see, it almost separates at random, creating the look of a green water bottom.
Now is the super cheap part- collect some rocks. I don't care from where, and I certainly won't tell anyone you took 'em, but rocks are everywhere. Break them up into manageable pieces using hammers or various vices. Glue one or two into each of the base areas for a place your model is going to be standing. I also painted the outside area black.
Mixing Woodland Scenics various static grass flock, such as harvest gold, light green, and medium green, I was able to create grassy areas where the grass didn't seem all the same. I also included Secret Weapon Miniatures leaf litter to add the extra variety needed.
In order to add some depth to the grassy areas, took the same mix above and stirred in some Elmers multi purpose glue (aka white glue). Taking bunches of that, I added them to the base, covering any areas which might need a bit more grass to hide the gaps.
Finally, the two above images show the Realistic Water added to the bases. This was easily the part which took the longest as Realistic Water has a habit of shrinking... a lot. In some areas it took 5 fillings to remove the areas in which the Realistic water pulled away.
As of now I have 25 bases. Hopefully I can find a faster way to create these bases and get them ready for the invading Chaos force which will occupy them!