Spell Focusing
Spell Focusing is an item property found on some items that causes the damage inflicted to start off below normal (-20%) but steadily rises until it reaches a +20% bonus. In effect, initial damage is lower than normal, but eventually reaches a point where the next five spells will be highly powerful before the cycle ends and begins to repeat.
A strategy for employing this property is to use low mana spells to build up the property's effect to the 5-spell max damage range and then use high mana/damage spells for five extremely powerful attacks.