Arcane efficiency (3.5e Feat)
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Arcane Efficiency [metamagic]
Many years of casting the same spells you have learned to use them move effective than others.
Prerequisite: Any Spell Focus, ability to cast 5th arcane spells, must have three 5th level or higher spell with the same school chosen for spell focus
Benefit: Spells cast with the same selected school chosen for spell focus have a +1 spell caster level. also, spell slot you must use to cast a metamagic spell in selected school is one level lower than normal.
Special: You May gain this feat multiple times. The effect stacks even with other feats, class abilities, and magical effects.