Practiced Invoker (Dragonfire Adept)

Type of Feat: General.
Prerequisite: Spellcraft 4.
Specifics: Your caster level for the chosen invoking class increases by 4. This benefit can't increase your caster level to higher than your Hit Dice. However, even if you can't benefit from the full bonus immediately, if you later gain Hit Dice in levels of noninvoking classes, you might be able to apply the rest of the bonus.

For example, a human 5th-level warlock/3rd-level fighter who selects this feat would increase his warlock caster level from 5th to 8th (since he has 8 Hit Dice). If he later gained a fighter level, he would gain the remainder of the bonus and his warlock caster level would become 9th (since he now has 9 Hit Dice).

This feat does not affect your invocations per day or invocations known. It increases your caster level only, which would help you penetrate spell resistance and increase the duration and other effects of your invocations.
Use: Automatic.