> Long series tend to become less and less interesting, and weirder as they go along
Malazan Book of the Fallen. ~3.325.000 words (200-400k per book) and the best series I've read in my life. Not the easiest to read with pretty complex story lines, somewhat weird timelines (see the Chronological order [1]) and certainly not the easiest book for a non-native speaker (never did I have to look up that many words) but rewarding and gripping until the very end.