The Shadowfey are split into two factions, the Fallen and the True. The "True" Shadowfey are grey skinned with blue armor and, assuming they don't die in combat, through magic have been able to achieve eternal life. This came at the cost of having children. Many of the True Shadowfey have became aloof, uncaring and cruel. The "Fallen" with red armor and normal skin tone abandoned their power and returned the normal cycle of birth and death. The Fallen tend to be more friendly with the Kingdom of Man, who they refer to as "Brightlanders". The two Shadowfey factions are mortal enemies.
There is a special enchantment called the Shadowfey enchantment. It is found on weapons with dark green icon backgrounds. These can be obtained from completing Boudica's quests, or from Elite Scrolls.