The electrical energy contained within your magic rages inside you, begging to be released.
Prerequisite: Ability to cast 3rdlevel spells.
Benefit: As long as you have an electricity spell of 3rd level or higher available to cast, you can fire a 20-foot line of electricity as a standard action. This bolt deals 1d6 points of electricity damage per level of the highest-level electricity spell you have available to cast.
As a secondary benefit, you gain a +1 competence bonus to your caster level when casting electricity spells.
Source: Complete Mage, page 47.