Absolutely amazing. I remembered this being my favourite for a long time when I was a kid, and I can see why. This is such a massive step up from the previous books in the series. Pyramids had something to say about tradition and dogma, this has something to say about human beings. The characters have significantly more depth to them, and the plot threads are followed in more detail and tie together brilliantly.
Also it’s hilarious. I particularly laughed at 32 people dying because of an attempt to stone a cloud to death.