Ah. The mighty gourselk. You may have been wondering about them if you read the short story, Cassien’s Dishonor, a few weeks ago. Gourselks are a creature that I actually created on the fly for that story. The gourselk is a staple creature of the underdark and is largely docile. When I created it, the gourselk is essentially the cow of the drow.
So, what exactly is a gourselk? Well, a gourselk is a large creature, typically 3 to 4 feet tall, 6 to 8 feet long, and weighing between 800 and 1300 pounds as an adult. They are fairly slow moving creatures and resemble a sea cucumber. They live on a diet that mostly consists of mushrooms that grow naturally underground. Depending on the area, gourselks can also be used to combat problems with mildew and algae that forms in damper caverns. Unlike the cows that are inspiration for them, gourselks cannot be milked. Their main use for the drow is a food source. It doesn’t really resemble meat as we know it, but gourselks are “meaty”, though the texture would be closer to tofu.
I do not currently have a stat block for running a game with these creatures, but do intend to make them available through DNDBeyond. You can find homebrew material created by me by searching for the author Erylia_DM there.