Definitely a lot of horror elements in the few I’ve read (Children of Time + sequels, Cage of Souls). I’ve only just scratched the surface, the man is a writing machine, but it does seem to be a trend so far.

He blends genres a lot and even his own work is kind of eclectic and all over the place, but his worldbuilding and the ability to take a totally alien concept and make it utterly believable are just top notch.