Oh man, where to start with this book...it was fantastic! 
 The beginning started off a little slow, I think that was only because I had to get back into the world of the Red Queen series and it took me a while to remember what had happened. After that it picked up pretty quickly. The characters were/are phenomenal. And even though the book is in Mare's perspective the entire time, we still got insight on the other characters. There were a lot more characters introduced in this book and they all had different personalities. The way Victoria Aveyard wrote the characters dialogue was fantastic and very smooth flowing. 
 (view spoiler)[The beginning of Glass Sword starts off where Red Queen ended. We find out more about the Scarlet Guard and what they have planned. At the end of Red Queen we see that Julian has discovered "Newbloods", both Red and Silver, people with red blood and silver abilities. He has written a list of all the Newbloods that he could find. At the end of Red Queen, Cal and Mare has just escaped the arena and Mare has the list, her mission is to find the Newbloods and get them to help fight with the Scarlet Guard. At the beginning of Glass Sword, Mare and Cal are rescued and brought to an island, a Scarlet Guard safe place. Cal ends of being imprisoned, shortly followed by Mare. They escape with the help of Shade, Kilorn, and Farley, and set off on a journey to get all the Newbloods before Maven has a chance to kill them, imprison them, or worse; torture them. This goes on for a while with some losses, a lot of gains. We come to the end where Mare and her crew infiltrate a prison, that Maven had built for all the Newbloods he captured and those Silvers that defied him, run by the Silvers, and free everyone with deaths of Reds, Newbloods, and Silvers in between. Queen Elara among the dead Silvers. Shade among the dead Newbloods. They get back to the safe island and hold funerals for all those who have died, Shade among the dead. Mare and her crew with some others go on a mission to help the cause of the Scarlet Guard when Maven stops them and Mare is forced to cut a deal with Maven to save everyone she loves and cares about. At the very end, we see her broken and weakened to Maven's dog, kneeling down to bow to King Maven. (hide spoiler)] 
 I really enjoyed Glass Sword up until the end that is... 
 1) because it ended and Lord knows I need more of the red queen world, and 
 2) that freaking twist! I mean seriously Victoria Aveyard is the QUEEN of twists and breaking your heart. 
 My only complaint about Glass Sword was that it took a little while to get back into the series, but once I was in it, I was in it til the end! Saying that, I cannot wait until the third book come out. And I salute you Queen Aveyard! 
 HAPPY READINGS!!!