Fortune is Fickle

(Rule)
Description: Casting Value: 7+  Remains in play. This may be cast on an enemy Wizard within 24" of the caster and may be cast into close combat. Whenever the victim rolls any double (even a double 6) to cast a spell it is a Miscast. In addition, any double rolled by the opposing player whilst attempting to dispel will fail (even a double 6). The spell lasts until it is dispelled, the Mage chooses to end it (which he can do at any time), attempts to cast another spell, or is slain.