Most spells are over in moments but some continue to exert their supernatural influence for several rounds. These are durational spells.
Some durational spells, like Moonglow, have a fixed duration but others, like Weaken, have a variable duration, indicated in the spell duration as requiring a Spell Expiry Roll.
Spell Expiry Rolls
Spell Expiry Rolls are made at the end of every combat round, including the round in which the spell was cast, and are resolved using two six-sided dice (2d6).
If the result of the 2d6 is a 12, the spell expires.
This roll must be made individually for each spell with a variable duration still operating.
- To reduce book-keeping outside combat, spell expiry rolls can be made per minute, instead of per round. There is a 75% chance that a durational spell subject to a Spell Expiry Roll will still be operating after 1 minute (10 combat rounds).
Durational spells may be terminated by their caster before they expire naturally. If a durational spell was cast using Magic Points and the caster terminates the spell before a Spell Expiry Roll would indicate it terminates naturally, the caster recovers half of the Magic Points used to cast the spell (rounded down).
- Mystics, who do not cast spells using Magic Points, get no value from terminating spells early. They do not, for example, get a chance to recover from Psychic Fatigue by terminating a spell early.