Mouseheart was a delightful random read that I came across last year. It wasn't perfect, but it reminded me of my days reading Redwall and had a solid, well-written plot. I really enjoyed reading it and looked forward to other book in the series. Hopper's Destiny is the recently released sequel to Mouseheart. 
 Hopper's Destiny picks up almost where Mouseheart left off. Hopper, our hero, is struggling to figure out how he is going to help the citizens of Atlantia. The battle that occurred in the first book may be over, but peace may not last forever and the citizens of the city are not prepared to fight. Hopper believes that the only way to succeed is to work with the outcast Mus encampment that is currently being run by his sister, Pinkie. Unfortunately, things do not go as planned. 
 Somehow, upon returning from his meeting with Pinkie, Hopper is transported to the Upland, where he meets new friends who will prove helpful in the upcoming final battle against Queen Felina. 
 Overall, I felt Hopper's Destiny was just as strong as Mouseheart. It had solid writing, it was fast paced, and the characters were evolving from the first book. The battle scenes were detailed and didn't border on the grotesque. I really enjoyed seeing how the characters drew out some of the battle strategies and planned for certain events. 
 I was really glad to see that the author took the time to make sure that not all cats were portrayed in a mean or evil way. As the story progressed, there were cats that were good, cats that were indifferent. It was a little disheartening to see that every cat in the first book was mean. 
 Most of the loose ends from the first book are tied up nicely in Hopper's Destiny. The whole La Rocha aspect of the series is explored and explained (fairly) satisfactory. There are some aspects of Hopper's Destiny that are left unresolved and we have to wait for the next installment, but the ending was satisfactory. It felt complete and not a huge cliffhanger. 
 Even though Hopper's Destiny was a strong book, it wasn't without its flaws. One of the biggest issues I had, which was similar to Mouseheart, was the way the mice/characters would do certain things. It didn't make sense to me, unless they were mutant mice. 
 For example, Hopper is a mouse. He isn't a giant rat; he is a normal, regular mouse. There is a scene in which he flings an extension cord up and over his head. The cord flies through a mail slot and he uses it to climb up and out of the mail slot. I struggle to see how a mouse could pick up an extension cord (used by humans) and toss it unless it was a mutant. 
 The scene above is in direct contrast to the other references to the animals/characters size. There is a beautifully drawn photo of a mouse in a small bed and behind it are human earrings used as wall hangings. It seemed the sizes were disproportionate to what was going on. If earrings were used as wall hangings, how was an extension cord so easily used? 
 I don't think the size issue is something children would notice, but I think older readers would definitely question it. Sure, we are talking about talking animals and animals with human-like behaviors, but I just think the portrayal could have been a little more realistic. 
 Another issue I ran into, and this is purely personal preference, was Pup (the younger brother of Pinkie and Hopper). He was so mean and damaged throughout the novel, but I didn't understand his anger. It seemed a bit of a forced element to the book, as he just seemed angry or damaged for the sake of plot progression. 
 Essentially Hopper's Destiny is a solid second book in a series. Younger readers, who may not be as critical of the character portrayal or somewhat predictable nature of some of the plot elements, will certainly enjoy it. Older readers, especially those that loved Redwall and Warriors, will still continue to enjoy the series. 
 Personally, I am still enjoying the Mouseheart series. This is certainly a second book in a series. It didn't wow me, but it was solid and moved certain plot elements along. I'm certainly on board for book three.