Have you ever heard of a game called Dwarf Fortress?
Perhaps my favorite dwarf game to exist, they use procedural generation to create terrible boss monsters known as Megabeasts that will attack your dwarfs.
I'd love to see some content like that, where we can fight some randomly generated boss monsters. One time you go down to the ruins of Camdozaal you find a giant, blue, three eyed lobster that shoots fire balls, the next time you get a two headed cyclopes that's oozes poison.
Is that something the code could even handle?