Back when new Ice and Fire books were coming at a steady pace (and then a not-so-steady pace, but still some pace), Martin was peppering installments of a spinoff in between. A series of novellas (short stories even, by his standards) was telling another tale in the same world, from nearly 100 years before the events of A Game of Thrones. An unlikely knight called Dunk and his even more unlikely squire Egg wandered Westeros and got into tiny (mis)adventures out on the margins of the kingdom's power struggles.
Over the course of three novellas, published in various short story collections featuring multiple authors, Martin told more focused stories with fewer characters. They weren't quite a continuing saga, though the tales did build on one another. They weren't exactly any cliffhangers, though there was the sense that there was some grander end to the story coming after some number of additional installments. But, just as with the main Ice and Fire books, Martin just sort of stopped writing at some point. (2010, in this case.)
The publishers, of course, need more George R.R. Martin books, whether he deigns to write them or not. So at one point, a few years back, they decided to collect the three existing Dunk and Egg adventures into one volume dubbed A Knight of the Seven Kingdoms. The three novellas together comprised a roughly novel-length book (if a touch short for most fantasy). And they were punched up with over 160 black-and-white illustrations by artist Gary Gianni.
The three tales overall are pretty good. Martin does have a way with words, and his writing is very vivid and evocative. Beautiful as the Gianni illustrations often are, they are in many cases superfluous, as Martin describes the scene so effectively that you look at a drawing and think, "yep, that's what I imagined." In this shorter format, where all the storytelling focuses on just one character's point of view, some of Martin's "tricks" are somewhat easier to spot. His use of repetition to cement a personality seems a bit more... well... repetitive. His lavish detail in describing food seems more clearly a predilection of Martin himself and not a trait of a character. But generally, I find I'm just drawn in, remembering part of what I loved about Martin's books in the first place.
The first tale, The Hedge Knight, is the strongest of the three. Its tale of an arena battle feels dangerous, high stakes, and visceral. All three tales are worthwhile, though. The Sworn Sword is an interesting story where the trouble at hand doesn't call for Dunk's strengths. The Mystery Knight is more of a tale of intrigue... though the pacing is not as well-managed as in the first two tales. Not all of these stories were easy to get your hands on before they were assembled in this one volume, though, so I was glad to have the collection.
I'd give A Knight of the Seven Kingdoms a B+. It's no Ice and Fire, of course. And you may well have made the decision that you won't give any more of your money to George R.R. Martin until it's for The Winds of Winter. But if you haven't, and you also haven't read the tales of Dunk and Egg, I'd recommend you check them out.