Any combination of three runestones can be branded onto a silver sword by a blacksmith to create a rune sword with different effects.
- In Chapter III, found on the corpse between the 2nd and 3rd archways in the Kikimore queen's lair.
- In Chapter IV:
- In Chapter V
- sold by the fence.
- found in a chest in the courtyard of the old manor.
- found in Agnes of Glanville's trunk.
Geralt starts the game with one moon rune. Later, they can be purchased from a number of merchants, including the mysterious merchant, Haggard or Thorak in Vergen, or Falas, the Incredible Lockhart or Polycarp of Rinde during Chapter III.
To use a rune, Geralt simply drags it over to one of the rune slots on a suitable sword in the inventory panel.
Moon runes can also be used to craft blue, red or yellow meteorite ore, though given that the price of a rune is significantly higher than that of a piece of ore, it seems a poor use of the rune.