I think when people mean that Discworld books have become darker they really mean the series is growing up. In 'The Colour of Magic' most of the city is set alight. It's a joke, in much the same way that the Earth is destroyed almost at the start of Douglas Adams's 'The Hitchhikers Guide to the Galaxy.'

The characters are the plot. What they do and say and the things that happen to them are, in a sense, what the plot is. You can't take character and plot apart from each other, really.

Fresh wounds," said Angua. "But one of them did shoot one of the other in the leg by accident." "I think you'd better put in your report as -self inflicted- wounds while resisting arrest," said Vimes.

Vimes had got around to a Clean Desk policy. It was a Clean Floor strategy that eluded him at the moment.

But what's worth more than gold?" "Practically everything. You, for example. Gold is heavy. Your weight in gold is not very much gold at all. Aren't you worth more than that?

Learnin’ how not to do things is as hard as learning how to do them.

I'd like to sell a lot of books.