Widen Spell

Type: Metamagic
Sources: Player's Handbook
Magic of Faerûn
Tome and Blood
Deities and Demigods

You can increase the area of your spells.
Benefit: You can alter a burst, emanation, line, or spread-shaped spell to increase its area. Any numeric measurements of the spell's area increase by 100%. For example, a fireball spell (which normally produces an 20-foot-radius spread) that is widened now fills a 40-foot-radius spread. A widened spell uses up a spell slot three levels higher than the spall's actual level.
Spells that do not have an area of one of these four sorts are not affected by this feat.