I started reading the Witcher books and obviously Ciri is headed to fulfill some kind of prophecy. However, that's also the plot of the last game. I understand that the games are a non-canonical continuation, but does that mean we don't get a satisfying conclusion to the last book? Please answer without spoiling it, I'm only interested if the prophecy's conclusion is the same as in the games.
An important thing one must accept when reading The Witcher, is the fact that Sapkowski apparently did not aim to answer some question conclusively; you may see here and here that questions asking about what really happened will not have definitive answers (the links I provided, as well as other Witcher questions here contain tons of spoilers!).
But I'll try to answer anyway.
In crudest terms, Ciri was meant to bear a male child who would be the "Avenger" (idk, that's what it said in Russian version). This person would save the inhabitants of her world from the White Frost. This is the reason why
- the Aen Elle,
- Vilgefortz of Roggeveen,
- Emhyr var Emreis
- and the Lodge of Sorceresses
seek her - each wants to manipulate her to conceive a child and then use it for their dirty stuff. Of them all, Vilgefortz was the coolest, because he simply wanted to
impregnate her with a needle and then cut out her placenta
Anyways, you are right - we do get a somewhat dissatisfying conclusion - at least we could call it that way - because Ciri's part in the whole thing isn't explicitly stated (we do get a hint from Nimue in the Lady of the Lake, but that's a spoiler).
Games try to finish that storyline - there are 3 choices (to my knowledge), which are all somewhere on the Internet (spoilers, obviously).
It is perhaps enough to say that you get to decide whether the prophecy plays the way it was foreseen or not; maybe not in a way you'd expect it though.
The original prophecy text is:
"The Wolf's Blizzard approaches, the time of the sword and axe. The Time of the White Frost and White Light, the Time of Madness and Disdain, Tedd Deireadh, the Final Age. The world will perish amidst ice and be reborn with the new sun. Reborn of the Elder Blood, of Hen Ichaer, of a planted seed. A seed that will not sprout but burst into flames!"
That prophecy is strengthened by Falka's last words:
"Avenger will be born from my blood! - she shouted - "Born from the cursed Elder Blood destroyer of nations and worlds! He will avenge my death!"
So it doesn't mention Ciri, but someone born from the "Elder Blood", or to be precisely a male offspring of someone having the "active" gene of Elder Blood, that is passed down among humans since Lara Dorren.
In the games, Ciri's destined role is to
Defeat the White Frost, which is some sort of Eldritch Abomination that moves between words and freezing them.
The book is little bit anticlimactic:
Yes, there is a "white frost" coming in the form of new ice age - the northern ports already started freezing during winter - but it will take a long, long time (Nimue thinks it will take about 3000 years).
So Ciri is not really destined to do anything, except possibly being mother (or maybe grandmother? Grand-grand mother?) to the "Destroyer of nations", but even that might be not true, since Ciri is not related by blood to Falka *.
Although, if she would marry
emperor Emrys (yes, her father - but she doesn't remember him) - in the book he is looking for her and wants to marry her for political reasons
her offspring would indeed rule huge empire.
* Ciri is related directly to Riannon - daughter of Lara Dorren and human Cregennan of Lod. She was adopted by queen Cerro, second wife of king Vridank. Falka was the daughter from the first marriage and after bloody rebellion she killed her father, two stepbrothers and imprisoned pregnant Riannon. Falka was at that time pregnant as well and when she gave birth, she gave the child to Riannon, which (after Falka's death) has risen all three children as her own. While wizards were able to find which child was Falka's, they kept the secret to avoid execution of a baby.
Falka's daughter, Adela, died at the age of 17 while helping sick during a plague