"Whilst there are some naturally occurring areas that lead to the combination and stagnation of magic into True Dhar, these areas tend to be flukes and are generally temporary, lasting anywhere from just a couple years to a couple of centuries. However, if a Henge can be corrupted, magic continues to flow into it indefinitely, never leaving unless actively drawn out by a spellcaster. This would mean that the Henge would have an ever-growing and ever more stagnant and destructive supply of Dhar, killing all life within proximity to the Henge and perhaps even coalescing slowly over the millennia into Warpstone."
"Warpstone is solidified magic and is a hideously dangerous substance. Although it is solid and has density, mass, and dimension, Warpstone is not made of any of the elements of physical existence. It is entirely its own thing. The Orders of Magic believe that if left undisturbed in an area long enough, Warpstone, like magic, undergoes a transformation from the pure substance in first appears as, to an even more destructive and dangerous tainted form. Warpstone is rare and important because it is the bridge between the material and the immaterial—it is a stuff of both pure magic, and physical existence.
The extraordinarily rare substance of Warpstone was discovered by the Empire and was given the nickname "Wyrdstone" after the destruction of Mordheim by a large meteorite of the stuff around five centuries ago.
In Warpstone, all the colours of magic become temporally and physically manifest in such a way that any sentient creature can see it, touch it, and utilise its power simply by holding it or standing near to it and concentrating. But Warpstone is incredibly dangerous because it actually leaks magic into the surrounding environment, saturating everything around it with its energy.
This saturation manifests in the forms of spontaneous mutation, the warping of solid forms, the manifestation of dreams, memories, fears, various psychoses, and other random and supernatural happenings. In this way, the effects of the physical presence of Warpstone are the same as the ill effects that come from using Dark Magic, only much more acute. The presence of Warpstone always causes these manifestations, unless stored in a thick magically null box or some other magically null container.
No one is entirely sure how Warpstone came into existence. One theory offered by the Loremasters of Hoeth suggests Warpstone was a substance first created by the pre-historic Old Ones to power their inexplicable arcane devices, like the Chaos Gates. The Loremasters theorise that when whatever catastrophe overtook the Old Ones, the great power source was ejected from its place between both the material and immaterial universes.
Pure Warpstone, then, is thought to be all the Winds of Magic made into a solid with an extremely random and dangerous influence over all things it touches. In addition to leaking magic into the environment, Warpstone actually draws the Winds of Magic to itself so they swirl around it like a mini-vortex. Depending on the size, age, nature, and positioning of a chunk of Warpstone it can play all manner of tricks upon those with witchsight. Some Wizards have reported becoming blinded by the foul rock, while others claim the substance causes ripples in their visions.
Once Warpstone comes to rest upon the mortal world, it attracts to itself the Winds of Magic, sucking them into its core and crushing them together. The longer this goes on, the more dangerous and tainted the Warpstone becomes. The Golden Order regards Warpstone that has sat upon or within the mortal world for any length of time as tainted and increasingly dangerous. Such ancient and tainted Warpstone (as was used by Nagash the Black during his blasphemous experimentations so many millennia ago) cannot create any effect other than ones that are destructive or dominating in nature.
The longer Warpstone resides on the mortal world, the more it absorbs and crushes the Winds of Magic into itself, in essence becoming solidified Dhar instead of solidified High Magic. Such ancient and tainted Warpstone may have less facility to work bizarre and wondrous miracles than it would to manifest horrific and hideous change or mutation. Ancient Warpstone is very bad news and is sought after and used only by the most powerful and insane Human magic users. Terrible immortals and semi-immortals like vampires and Dark Elves, or the Chaos mutants known as Skaven, also pursue Warpstone for their own wicked ends. However, whether freshly arrived upon the mortal world in the form of a meteorite or whether it has rested deep in a mountain for millennia, Warpstone is best avoided at all costs."
