Choose a school of magic to which you already have applied the Spell Focus feat. Your spells of that school are even more potent than normal.
Benefit: Add +1 to the difficulty class for all saving throws against spells from the school of magic you select to focus on. This bonus stacks with the bonus from Spell Focus.
Special: You can gain this feat multiple times. Its effects do not stack. Each time you take the feat, it applies to a new school of magic to which you have already applied the Spell Focus feat.