Mattimeo was a decent book, but Brian Jacques managed to keep the series fresh by writing a story that originates outside of Redwall Abbey, but still with some of the story set at Redwall with characters we know and love. One nice thing is that the protagonist of this book (and the title of this book) is a female, so it was a good way to bring in female readers. The villains and plotline in this story feel real (for talking animals, at least) and this book really illustrated that Jacques was a solid author who could keep things interesting. The bit with the bell is also fascinating, and this book serves as an satisfying installment in the history/timeline of the Redwall saga.
I feel kinda sorry saying this because of Jacques' clear love for Redwall, but this installment is trash. It's dull, the characters are horrible (Mariel is an obnoxious and egotistical bitch, who almost gets Lord Rawnblade killed because she screams at him and distracts him during a deadly battle - why the f would she do that? - the Dibbuns are f-ing annoying and I hate that shitty baby talk strewn around the novel - and the searats are supposed to be fearless, experienced warriors but make the dumbest mistakes, can't battle for shit and follow a leader, who promises them clearly empty promises, no one with a sound mind would follow him, who also loses his mind out of nowhere), the events are... uneventful, deus ex machina's clutter the plot, characters get saved by the most random interventions, and for example Redwall has ZERO real damage after the rats throw fireballs for days; quickly assembled, inexperienced Redwall defenders that have never picked up a weapon before always hit/kill their targets on first strike, while the rats only strike walls. Also, nothing in this novel makes sense time-wise. Characters form the deepest bonds in literally 2 days, a prisoner gets emaciated in a literal week, some other things which I can't recall already. The only thing that was pleasant this time was the welcome lack of the Logalog shrews.
The worst offender is that every Redwall installment so far has honestly just been a carbon copy of the first. Is there any of the 22 installments that is different, suspenseful and enjoyable, and preferably does not contain both Redwall, annoying children and characters that speak like I say, bally bloomin' flippin' old jolly blighter gel, donchaknow? wot?, weeeeh me wants epples not pers abbo Berno or zoiiiiiduurrrr aving you'm baint no fun weading dis hurrrrrdurrr?