I've been nibbling round the edges of Pratchett's massive (40 plus) body of work for some time now but this is the first illustrated one I've read. and, oh! what a delight!
The setting is, of course, the Discworld which, as everyone knows is a disc with a mountain in the center and oceans and continents--all resting on the backs of four elephants which, in turn are atop the Great A'tuin, a celestial turtle swimming though space.
The last hero is Cohen the Barbarian, who is leading a band of-- well, they don't want to be called elderly but they all certainly have a keen interest in the location of the nearest rest stop-- let's say mature warriors to Dunmanifestin, the citadel of the gods, in order to prevent the end of the world.
And then it gets complicated.
Highly recommended.