The shader itself was based on Valve's DOTA 2 Shader Guide(PDF), from the DOTA Workshop page. Currently it is not using the R channel for the first map, the one that creates the detail texture. It should be added in the near future.
This map is not listed in the Workshop page, but I needed the 2 extra maps, since my textures lack the A Channel, due to ETC1 compression for Android.
And this is the node tree, from Shader Forge.