This tile is a preliminary attempt at producing an urban geomorph. I still don't have my system worked out completely, so I decided to make this one compatible with my existing set. I'll probably do a few more of these, as I have an old map of an underground city that I developed while I was in college. I think I'll need to post more about that setting later. For now I'll say that it was inspired by the old Wormy comic from Dragon, designed for straight-up fantasy, and implemented in a steam-age alternate alternate earth with pirates.
22 hours ago