This turned up in hardback, good dust cover, in a second hand shop for a couple of bucks, so I bought it. And read it. It is 15th sequel to Frank Herbert's fantastically good 1965 novel Dune. The sequels have been lesser works, pot boilers some would call them. This one is no exception. All though 512 pages long, it isn't really a novel in my view. It's a bunch of events, each event having little to tie it to it's sisters. The book does have a protagonist, or perhaps better explained as a view point character, namely Paul Atriedes (Muad'Dib). But Paul never does much, he is present in most of the events, but as a passive observer. Even in the final event, an attempt on his life, Paul does not even sentence the assassin to death. This is a far cry from Dune, where Paul escapes Harkonnen assassins, rallies the Fremen. overthrows the Galactic Emperor, and slays a couple of enemies hand to hand in formal duels with knives.
In a real novel, the protagonist is faced with some kind of challenge. He will make several attempts to overcome his challenge, in the last attempt, the climax of the novel, the protagonist will do or die, either triumph over his challenge or die from it. That doesn't happen here. There is no challenge to Paul Muad'Dib, he encounters a flock of bitter enemies, but nothing especial, nothing worthy of the attention of the new Galactic Emperor.
In short, after slogging thru 512 pages, bupkis.