Hunting the Wild Hunt

Hunting the Wild Hunt is a secondary quest in Act IV of The Witcher, set in the Fields around Murky Waters. Ask the hermit (the one in the hut past the barrows) about witcher work and he will tell you the Druids’ Circle has become a magnet for wraiths, and worse, that the King of the Wild Hunt himself now haunts it.

Since the King is far beyond anything a sword can handle, the hermit’s advice is to burn mandrake root at the circle to drive him off. Geralt then has to hold the circle at night against three waves of wraiths. The hermit pays with a pouch of salt that repels wraiths, plus one extra reward of Geralt’s choosing.

Walkthrough

Find the hermit in the Fields (his hut is past the barrows, not the first hut you see) and ask about witcher work.
Pick up mandrake root from the barrows next to his hut.
Go to the Druids’ Circle at night and fight the wraiths: three waves of three.
When the King of the Wild Hunt appears during the second or third wave, place the mandrake root in the lantern at the circle to make him retreat.
Clear the remaining wraiths and return to the hermit for the pouch of salt and your chosen reward.

Quest Consequences & Choices

Burning the mandrake makes the King of the Hunt withdraw; without it you are left facing him, which is not a fight worth picking.
The hermit lets you choose one extra reward: the book Vampires: Facts and Myths, a wreath of immortelles (needed for The Heat of the Day), or the hut next to his (which is mostly useless).