Such is your skill with channelling energy that you can boost any spell you cast with positive or negative energy making it more deadly.

Prerequisite(s): Channel energy class feature, Channeling Focus, Caster level 5th or higher

Benefit: As a swift action you can expend a channel energy use to increase the duration, area of effect or damage of any spell you cast by 50%; chosen when the spell is cast. This effect applies only to spell you cast this round.