Have to recommend this one, just because it has been one of my favorites for about 45 years.
This book has it all, heroes, villains, loyalty, espionage, action and even true. Also it has such incredible characters and dialogue.
They are conscious beings, but still rabbits, which is what I love so much and which sticks the book in the sci-fi genre for me. It's been a few years since I read jt, but that moment when they were crossing the river and one of the very basic rabbits couldn't even remember the crossing not 1 minute later because it was so outside their rabbity existence... Mwah! So good!
Every time I see a rabbit in the evening I think about their siflay.