Tiefling seem to be some sort of mutation of an otherwise human child. They have several physical mutations including large horns; thick, nonprehensile tails that range in length from four to five feet; sharply pointed teeth; and eyes that are solid orbs of black, red, white, silver, or gold. Their skin color covers the whole human range and also extends to reds, from a ruddy tan to a brick red. Their hair, cascading down behind their horns, is as likely to be dark blue, red, or purple as more common human colors.
The tiefling are a rarity in the world of Altha'Ruin and nobody know what causes this mutation. Many in the church believe that it is a curse from Exuro bathing the child in fire. Others believe that the birth of a tiefling is a sign of a great catastrophe or the price of making a deal with a demon. Wherever tiefling come from, they are usually met with fear and mistrust from a god fearing public. Those who can see past their physical appearance find them to be creative, intelligent, and natural leaders.