Just because Mannahnin mentioned a different book as a favourite, and that no one else seems to have put it forward as their favourite, mine is Legend by David Gemmell.
I don't think
Legend is particularly great in any of the ways I personally care about in a book, but it is definitely worth reading, and more importantly, I think it and Robin Hobb's
Assassin trilogy really significantly influenced the future direction of fantasy - also in 1984, Legend was pretty much unique. Had I read it back in the '80s or very early '90s I would have been pretty shocked by it. It's one of the first modern fantasy novels where the hero is aging and feeling the results of that, and really very much human, and with feet of clay, barely dragging themselves through the story, and I think there's a whole major subgenre of fantasy that basically exists because of that - very much much including people like Joe Abercrombie. I think part of the reason ASoIaF was so successful is the longer-term influence of
Legend and works it inspired or influenced. It's representative of a sort of reaction to Moorcock and Tolkien - there's perhaps some inspiration from Elric, who is himself not in a great state, but I think it's more that the protagonists in Legend really go through some stuff, in a very human way, that's not connected to magic or high weirdness in the way Frodo's struggle with the ring is, for example. And they're not confident, aloof and airy like the vast majority of Moorcock's characters ultimately are (even the doomed ones - maybe especially the doomed ones).
There's a fair bit of what might be cruelly termed OAP fantasy (bus pass fantasy? Too British?) around at the moment - featuring characters mostly in their 50s or a bit older, who were once young. Two big examples would be Robin Hobb again with the final* Assassin trilogy (the fourth? Technically called the Fitz and the Fool trilogy, I think), where the titular assassin, who we've followed since since he was a boy, through his teens, twenties and thirties in previous books, is now in his 50s, and yeah going through some stuff. And Tad Williams revisits Simon and co from Memory, Sorrow and Thorn "trilogy" (lol and the same thing happens again - we're about to get the fourth book of this "trilogy" too), and Simon isn't just a dad, he's a grandad, in I think his mid-late 50s, and man he ends up going through even more stuff, physical, mental, spiritual torment, the results of aging and time and events catching up with you. Abercrombie's stuff also has some of this with the older characters.
Whilst
Legend only sort of has a bit of that going on (but even the younger quasi-protagonist doubts himself and thinks he's a coward and so on), I really think it paved the way for these kind of books. And the tone is very close - as is the fact that, unlike a lot of epic fantasy, many of the antagonists are quite reasonable.
* = Sounds like there might be another one on the way, as of a recent comment by Hobb, but not focusing on Fitz nor the Fool.