I knew that I would love Pyramids from fairly early on. The initial stages of the book see the heir to a small and ancient desert kingdom being shipped off to join the Assassins Guild to 'gain valuable life experience'. One of the earlier scenes involves the protagonist, having now completed their basic training, taking the final exam which is structured just like a modern driving test ("proceed in your own time" etc). The sheer lunacy of this juxtaposition and the very relatable stress and anxiety experienced by the protagonist, right up to the "I don't actually want to kill people" moment, is exactly the sort of black and slightly insane humour that I enjoy.
It's a very strong start, but one not let down when the new pharaoh then has to return to his kingdom to take up the mantle of god king. I was obsessed with ancient Egypt for a few years in my youth and grew up amongst hippies and all manner of folk of a New Age persuasion; so Pratchett's irreverent take on sacred geometries and the wisdom of the ancients was pitch-perfect for me. His humour is at its best (so far) in this book; extremely well researched and lightly poking fun at its subject matter, but not overly condescending and very democratic in who is made fun of (no one is safe). Throwing in some wonderfully inventive gods, a witty exploration of what people's ancestors really think of them, and a few light horror tropes just makes the book all the better.
The characters are, perhaps, not quite as strong as in Wyrd Sisters, and the plot not as coherent, but it's still a wonderful book nonetheless. Definitely the funniest Discworld book so far, and, perhaps, my favourite.