In a lot of ways, fantasy series like this one are only as good as their final book. I think this is even more true for trilogies, probably because there’s less content to work with. It’s why I always told my students when I was teaching English Comp to make sure their conclusions were memorable. You could write the most brilliant essay ever (or book, or TV show — as we learned with Lost), and if you flub the ending, the rest of your content is somehow tainted. This isn’t true of all stories, but I think it is true to a certain extent, especially with stories like this one where all three books are part of a greater whole, deliberately constructed to tell one complete story with a beginning, middle and end.
All of that is to say that if Sanderson had flubbed this final book, and even more importantly, the last 100 pages or so, the other two books would have been colored in response, and I might have thought less of them and the series as a whole, if what they were leading up to was a dud. Thankfully — at least for me, although apparently the ending to The Hero of Ages did rather upset some people — he nails it. A good ending for me is one that ties a whole story together and illuminates things that happened previously in a new light. It resolves problems and gives you a strong idea of why the author was telling the story in the first place. Also, it makes you feel things. As far as I’m concerned, The Hero of Ages meets every requirement on that list.
I’m not going to go too far into the plot because that would ruin it. What I will say is that unless you’re really, really, really good at guessing endings, you’re going to be completely surprised by how it all turns out. Hopefully you’ll also get the nice sense of emotional fulfillment that I got out of it as well. Character arcs not only end satisfactorily but manage to combine to give an even greater satisfaction. Characters get the endings they deserve.
As a whole, despite how iffy I felt about book two (and to be honest the first 50 pages or so of this one), this series as a whole gets five stars from me. Can’t wait to explore the further novels Sanderson has written in this world (which I think take place about 300 years from the time in this trilogy).