[Thadlerian]

I consider Terry Pratchett's books great and important in fantasy.
He masters the language better that most writers I've read. At first his books are rather of the parodic sort, cocking a highly deserved snook at various fantasy generes.

But they soon turn into social and political satire, and pretty good so too. And they never seem to lose their wittiness. As you get characters returning from book to book, these get devolped pretty well too. I recommend starting at Mort or Guards! Guards!, as these two initiate the two best series.