This rotted wooden chalice is filled with a vile brew of blood and pus. Any Shaman that sups from it is wracked with pain, even as raw magic courses through their veins.
If the bearer of the Plague Chalice rolls any natural double when making a Casting roll (not including rolls of a natural double 1), the spell is cast as a perfect invocation, regardless of its casting value or of any other modifiers. However, each time the bearer casts a perfect invocation, they suffer a Strength 4 hit with no armour save permitted (Ward and Regeneration saves can be attempted as normal).