Warpstone

A crystalline substance appearing like silvery quartz and apparently created by power leakage from the tombs of Ahriman, under the mountains near Foxcourt, and Apollyon, in the Spawn's highland lake in central Terranova.

Warpstone appears to reflect, amplify, and randomly alter mana, resulting in highly unexpected thaumatugical effects in a similar manner to Kyanite Crystal. Sentient beings and animals appear more susceptible to its effects than plants or minerals, and the alterations can be both dramatic and permanent.

Some examples of observed alteration include: tentacle limbs; goat legs; feathers; snake body & legs; crab claws; natural armour; extra limbs; invisibility; breath weapons; sentience; and gigantism.

Unrefined warpstone naturally reflects spells cast at it, often causing these warpings in the caster or other nearby beings. Refined warpstone may be used to store mana, and also to channel mana to cause mutation effects.

Warpstones have also been reported on the Plane of Glorantha