Blood of elves - Andrzej Sapkowski

For more than a hundred years humans, dwarves, gnomes and elves lived together in relative peace. But times have changed, the uneasy peace is over and now the races once again fight each other - and themselves: dwarves are killing their kinsmen, and elves are murdering humans and elves, at least those elves who are friendly to humans . . .

Into this tumultuous time is born a child for whom the witchers of the world have been waiting. Ciri, the granddaughter of Queen Calanthe, the Lioness of Cintra, has strange powers and a stranger destiny, for prophecy names her the Flame, one with the power to change the world - for good, or for evil . . .
Geralt, the witcher of Rivia, has taken Ciri to the relative safety of the Witchers' Settlement, but it soon becomes clear that Ciri isn't like the other witchers. As the political situation grows ever dimmer and the threat of war hangs almost palpably over the land, Geralt searches for someone to train Ciri's unique powers. But someone else has an eye on the young girl, someone who understand exactly what the prophecy means - and exactly what Ciri's power can do.

This time Geralt may have met his match.