TWoS has roughly the same elements that can be found in other Shannara books: a source of evil, young members of the Ohmsford family and associated friends, an old druid who gets the whole plot moving, a quest to save the Four Lands from mentioned source of evil (that which made Brona into the Warlock Lord). Brooks has never varied this formula much, which is okay, since he has been able to use it for writing fantasy epics that cover the scale from good to great.
TWoS is more on the good than the great side, at times there’s too much routine in how the plot enfolds, and the good characters feel like variations on the same theme. Most of all, the source of evil wasn’t in the same class as the Warlock Lord (from FKoS) or the Demons. I didn’t got the feeling that the heroes had to fight overwhelming forces. Still, it’s a nice conclusion for the first three Shannara books.