If a character is lucky (or unlucky) enough to uncover a piece of Warpstone, he may desire to use it. As mentioned, Warpstone is very powerful, but it is also very dangerous, even more so by those who don't respect its power. Warpstone's effects depend upon the form in which it is found, as well as the quantity and degree of exposure involved.
• Warpstone Dust: Achieved by grinding Warpstone into a fine powder, for it to have its greatest effect it must be ingested. Generally used by Skaven Grey Seers, Warpstone Dust can enhance their ability to manipulate sorcerous energies. For those not inured to Warpstone, the effects are dangerous, causing all sorts of mutations.
Skaven treat Warpstone Dust as if they had consumed a Warpstone Token. For all others, subjects must succeed on a Toughness Test, the difficulty depending on the extent of contact.
• Very Easy (+30%): Spilling a small amount on clothing.
• Easy (+20%): Skin contact with a small amount.
• Routine (+10%): Skin contact with a moderate amount.
• Average (+0%): Swallowing or breathing in a small amount or skin contact with a large amount.
• Challenging (–10%): Swallowing or breathing in a moderate amount or skin contact with the whole amount.
• Hard (–20%): Swallowing or breathing in a large amount.
• Very Hard (–30%): Swallowing or breathing in the whole amount.
Any Character who fails his Toughness Test gains a mutation. Roll on Table 3–1: Mutations. Warpstone Dust has no other appreciable benefits.
• Warpstone Tokens: Warpstone Tokens are small pieces of Warpstone, occasionally shaped in disks but also in rings, wedges, or small blocks. Skaven eat them to aid in spell casting. Other characters that come into contact with a Warpstone Token must succeed on a Toughness Test or gain a mutation, rolling on Table 3–1: Mutations. It's generally impossible for non-Skaven to eat these Tokens, but if attempted, the individual must succeed on a Hard (–20%) Toughness Test to avoid gaining a mutation.
Assuming a character survives contact with a Warpstone Token intact, he can use the substance as an additional ingredient. Each Token used adds +3 to the next Casting Roll, but it also increases the risk of Tzeentch's Curse. Treat all doubles on Casting Rolls as triples, and all triples as quadruples.
• Unrefined Warpstone: Raw Warpstone is dangerous. A Character who touches unrefined Warpstone with naked flesh must succeed on a Toughness Test or lose 3 Wounds, of which 1 never heals. Also, the Character must succeed on a Hard (–20%) Toughness Test or gain a mutation.
Warlock Engineers, Master Moulders, and other villains in Skaven society treasure lodes of Unrefined Warpstone since they use it to create the most abominable creations, ranging from Warpfire Cannons to Rat Ogres. Casting spells within 6 yards (3 squares) of unrefined Warpstone gives a +6 bonus to Casting Rolls; however, casters must also throw an additional die called a Chaos Die. Do not apply this die towards the spell's Casting Number. Instead, it is used simply to increase the chances of Tzeentch's Curse. And, even worse, if the spell caster does roll doubles, he also gains a side effect as if he had used Dhar. See Chapter XVII: Chaos Sorcery in this book for more details.
