There might be something in the sewers.

This is a miniature I constructed from two separate and completely independent STLs which I printed. I added brass wire to make the bursted iron bars. I bent the wire and used a pin vice drill to drill holes in the sewer and then glued the tentacle to the sewer. As I downloaded the STLs months ago I forget their name and whether I obtained them from Thingiverse or Cults 3D. I used lichen texturing powder but it looks like patina. I also used three different color shift hobby paints for the tentacle.