While I'm firmly of the opinion that no Redwall novel is inherently bad (with the possible exception of Loamhedge, and that's only for its bat's arse stance on being able to 'cure' disability with the POWER OF POSITIVE THINKING) Taggerung doesn't live up to the high standards of its predecessors. It doesn't help that the plot is almost identical to that of Outcast of Redwall, already a fairly mediocre entry into the series, albeit it flipped on its head. This time it's a good creature being raised by vermin, and the results are even more predictable. It's never Veil's actions in Outcast that make his outcome certain, but the actions of everyone around him, convinced that as a ferret he'll turn out to be evil. In Taggerung, despite the fact that Deyna is raised by vermin he never once acts in ambiguous manner; his first on-page deed as an adult is to spare a creature's life. He doesn't even speak with a villainous accent. Maybe posh Abbey voices are genetic.
Once we've got the obviousness of Deyna's good character out of the way, we've got the Abbey plot, and it's another of those 'solve the riddles to find the new Abbey Leader' type of affairs. It's not a spoiler to tell you the Abbess will be Mhera because Cregga Badgermum tells Mhera it'll be her about five chapters into the novel, which really does render Mhera solving a load of puzzles and then being appointed leader at the end of the book completely pointless. I say puzzles, once the initial location riddle is solved, it just amounts to Mhera and her friends finding scraps of cloth with 'ITTAGALL' written on them all over the place. Don't worry, fair review reader, no-one knows what 'ITTAGALL' is supposed to mean, and when it's revealed at the end of the book it doesn't make a great deal of sense either. You know how they say a joke isn't funny if you have to explain it? Turns out a Redwall riddle doesn't work if you already know the outcome but people keep leaving bits of cloth everywhere. The 'Fifteen Seasons Later' concept, flinging all the characters ahead a few years is a great idea though.
What Taggerung does have over previous books is its cast of villains. We've got the suave, genre savvy Sawney Rath, scheming mother Antigra, her stupid son Gruven, the deadly tag team of Eefera and Vallug Bowbeast, and finally the terrifying Ruggan Bor. The Juska clan conceit feels really fresh and interesting, there's always this sense of danger just bubbling up under the main story. It's a shame then when, right at the end, Russano the Wise shows up out of nowhere and sends the main gang away, robbing us of an epic Abbey smack-down. Deus Ex Badger Machina does not a good resolution make.
With that said, there are a lot of things Taggerung does really well. Nimbalo is a deftly written and well rounded character, and his journey with Deyna through the flatlands is never less than engaging. Like that bit where they stop a gang of pygmy shrews making Wicker Man-like sacrifices to a giant eel, or when they reveal his dad was beating him as a child because whu-uuu-uuut the f*ck that came out of nowhere. Brutal. Cregga's death is one of the best written moments in the whole series, poignant and bittersweet. Her death lends the book a sense of finality as well; Taggerung marks the final Redwall book to feature recurring characters and not be set in a far-flung, non-specific future period. It's Triss after this. And we all know what Triss means. Nazi Ferrets. And not in a good way.
Also, and it's a small niggle, but I first read this book when I was eleven and it annoyed me then and it annoyed me again on this re-read so I'm pointing it out. When Mhera is OFFICIALLY announced as Abbess at the end of the book, one of her closest friends leans in and says 'best wishes from myself, Fwirl and Friar Bob.' That's not something you say to your best mate when they've just been offered the role of top dog! That's what you write in a card when your mum tells you your second cousin has just passed her driving test and you don't know her very well but you have to put something, otherwise it would be rude, right? It takes me RIGHT OUT of the story and I've been bothered by it for almost twenty years. I'm sorry.