Faerie folk are all roughly related, though their natures have diverged since the time when they could claim a common ancestor. Brownies, Leprechauns, Nixies, Pixies and Sylphs all take [D – 2] damage from physical contact with cold iron (due to burning) in addition to any other damage that may be inflicted by a weapon made of that substance. Other faerie folk do not suffer this effect, but prefer to use substances other than cold iron for tools and artefacts.
Only the Elves have overcome their fear of the substance to the extent of habitually forging and using fine iron and steel weapons. All faerie folk have witch-sight.
More information about their culture and habits can be found on the Fae page.