I've been following this series for awhile now. At one point, a few years ago, I was so addicted that I had to order the 3 books that had been released in the UK because I couldn't wait for the US versions to come out. So, it was with much pleasure and anticipation that I sat down to read books 10, 11, and 12 in one sitting.
I have to say that Book 12 left me a bit disappointed. At the end of the book, Shan has the main character go back in the time & prevent himself from making the mistake of kidnapping Madam Octa. Since Darren manages to stop himself from kidnapping the spider, he never makes the deal with Mr. Crepsley & ends up leading a normal, healthy, life as a human. This, of course, means that Darius is probably never born (because Annie wouldn't be a single mom at 16). But there is a possibility that others still die the same way -- Mr. Crepsley, Shancus... their fate may be the same, but Darren won't be around to witness it.
I understand that Shan felt that this was the only way to resolve the convoluted system of "Destiny" that he created in the past 11 books. However, in the process, it left the reader high and dry because the ending basically told us that the stories we had just invested time and effort in for the past few years didn't happen. Sure, they would still happen in a way -- but these trials and tribulations wouldn't fall on a boy named Darren Shan. Some other, nameless, person would step up to take over Darren's destiny. And we're just supposed to leave to our imagination how the universe righted itself & who was affected by the change in the end. Will the ones who died still end up dead? Will this new child (whoever it is) end up sacrificing themselves & floating to Paradise (as Darren predicts he/she would) or, maybe, they cannot resist the lure that Mr. Tiny places on them.
The biggest issue I have with this ending is that it makes us wonder -- why'd we read the past 11 books if they were all irrelevant? This is the equivalent of Shan ending the series with a scene where Darren wakes up from a nightmare and finds out it was all a dream. I invested time and emotion in Darren's Saga. And now you're telling me that it wasn't Darren's saga, at all. And, perhaps, even the people mentioned in the book might not have had anything to do with it, because Darren changed the course of history.
Another thing that bothered me were the holes in the whole "fate vs. destiny" situation. Darren managed to overcome the two set futures by killing himself and Steve. However -- why didn't he just have the power to "Just Say No" to Des Tiny's edicts? Why not just say, "Thanks, but no thanks, I choose my own fate and I don't want to rule the world." Particularly when he'd already been shown the consequences his actions if he did get mixed up with Mr. Tiny's vision. The author was feeding us two messages: (1) You control on your fate in a manner of speaking and should choose the path of good, but (2) If Mr. Tiny makes you evil, there's nothing you can do about it. I was like, "huh??" Not to mention -- Mr. Tiny had waaaayyy too much power & I didn't like the fact that he wasn't facing any consequences for his actions.
Also, why did Darren go the Lake of Souls... he was a decent guy and sacrificed himself. I didn't buy the whole "guilt" thing. Other vampires had probably done much more bad things in their long lives (like Mr. Crepsley) and they went straight to Paradise. It made no sense that Darren -- a half-Vampire who constantly did the ethical thing -- would end up in the Lake of Souls for hundreds of thousands of years & there would be no force in the universe that could right that mistake. Again, giving Mr. Tiny way too much power.
Basically, I give this 3.5 stars because the series, as a whole, is excellent. And, naturally, if you read Books 1-11, you have to read this finale. However, this particular reader was left unsatisfied with the resolution of the series. I was hoping for more closure.