Lord of Chaos probably has more big developments than any pre-Sanderson book.
SPOILERS
When you consider that the Black Tower was formed in LoC and that the by end of the book Dumai's Wells happens...that's a lot of progress in one book. Also Egwene became Amyrlin and I feel like I'm forgetting a lot of other things. I remember there being a lot of stuff involving Forsaken which I always enjoy.
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