Warlock Holmes, book 2: The Hell-Hound of the Baskervilles
G. S. Denning2017

The game's afoot once more as the long-suffering Dr. John Watson and a partially-decomposed Warlock Holmes (though he's getting better) face off against Moriarty's gang, the Pinkertons, flesh-eating horses, a parliament of imps, boredom, Surrey, a succubus, an overly-Canadian aristocrat, a tricycle-fight to the death and the dreaded Pumpcrow. Oh, and a hell-hound, one assumes.