The Skaven were born of the union of Chaos and Dark Magic in the days following the collapse of the warp gates and the Time of Chaos. When the winds of magic blow strongly the Skaven race multiples: in the tunnels and caverns beneath the cities of men, Skaven numbers swell, and their great under-empire spreads like a dark plague. At such times Skaven Seers cast earth-shattering magic such as brought down the old Dwarf Empire in a cataclysm of volcanic eruption and earthquake.

The Skaven worship their own dark god the Horned Rat, the manifestation of their evil schemes to consume the world. Skaven magic draws upon the dark power of evil magic. The Skaven supplement this power with warpstone - concentrated pieces of black energy blown into the world by howling winds of magic during the collapse of the warp gates. These small chunks of stone radiate malign power, causing the mutation and corruption of mortal flesh.

Only a Skaven can touch warpstone without immediately suffering from its mutating effects, and even they become twisted and warped by its energy eventually. A Skaven sorcerer can consume small lumps of warpstone during the battle and feed upon its power to fuel his spells.

There are two kinds of Skaven sorcerers. The most powerful are the Grey Seers, the lords and masters of the Skaven race, second only in power to the Great Council of the Thirteen Lords of Decay. The lesser kind of sorcerers are the Warlocks who belong to the Clan Skryre. Where human wizards learn their magic in the Colleges of Magic in the Empire, the Skaven Clan Skryre pursues the study of spell casting and enchantment. As well as learning potent spells the Warlocks create devices which merge technology and magic.