The first set of materials that I wanted to make on my own in Substance Designer had a bit of an alien theme going on. This one was a mix of a beehive and some sort of scifi growth chamber. Fun material to make, but the vines/veins took a bit to get right.
You can find the SBSAR on Gumroad here: https://gumroad.com/l/jVkBP
And see all my Substances here: https://gumroad.com/_dc_