Mirabilis: Year of Wonders sees hero Jack Ember facing a different adversary, but overarching all four seasons is the Big Bad who will present Jack with his most personal and fraught challenges. The Kind Gentleman is not overtly the Devil, but Jack's mentor Talisin at one point calls him "humanity's darkest dream" and - well, draw your own conclusions from that.
Some people have described Mirabilis as steampunk, but it isn't that at all. In the world of Mirabilis, everything is coming true. Whatever has been dreamt up by mortal minds over the millennia is given substance by the green comet that heralds this annus mirabilis.
Leo Hartas, Martin McKenna and I planned it as a vast storyline incorporating horror, faerie, whimsy, mythology and dream. There is Victorian and Edwardian science fiction, with murderous brains in tripods and stuff, but I wouldn't actually call that steampunk any more than I'd say the Green Knight sells sweetcorn.
Anyway, we were talking about Old Nick recently, so I thought you might enjoy this glimpse of what happens if you annoy the Kind Gentleman when he's trying to watch a slideshow. Personally, I have a lot of sympathy.