Triumph of the Darksword

Triumph of the Darksword by Margaret Weis and Tracy Hickman

Barnes and Nobles Description:

Joram and his wife, Gwendolyn, return from beyond the Border to reclaim their rightful place in Merilon. Rejoined by Saryon, Mosiah and Simkin, Joram must confront the evil sorcerer, Menju, and his army of Technologists in a final apocalyptic battle to fulfill the ancient prophecy of the Darksword--to either save the world.  

That was not the best description in the world on but I suppose that is what they wrote since it is the third book? 
This trilogy turned out to be great!  I would've never picked up these books if a friend hadn't given them to me as a gift.  These books are older, written in the late 90s so I didn't even know about them.  There were some flaws in the last book, like the best character ever gets killed off fast and for no reason.  I have been reading reviews about this book and most people don't seem to like it.  I like how it went from magical (the first two books) to sci-fi.  I found out that there is a 4th book... I am wondering if the authors saw that people didn't like the ending of this book.  I don't know how I can't read this book?  I mean... obviously when an author adds a 4th book to a trilogy how do you not read it and get to see what happens? So we will see if I pick it up or not? Hoping the library has it!