A lasting spell’s effect is a natural part of reality; it has no defined Duration, since it persists as long as it is natural for it to. For example, a spell that sets a target on fire is lasting. The fire is real and continues
to burn normally until it is put out or there’s nothing left to burn. The target’s injuries are also real and must heal normally. Likewise, a spell that heals injuries is lasting. The healing restores the target to its natural state, so wounds do not re-appear when the spell ends.
Concentration-based, transitory and prolonged spells all create an unnatural effect, such as transforming someone’s shape. Their effects end once the spell’s Duration expires. That is, reality restores things to normal. Spells with a lasting Duration do not count against the maximum number of spells a mage can maintain (based on his Gnosis).
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