Practiced Invocation (3.5e Feat)
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Benefit: Your Invoker level for your Invoker class increases by 4. This benefit can’t increase your invoker level to higher than your Effective Character Level. However, even if you can’t benefit from the full bonus immediately, if you later gain ECL in levels of non-invocating 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 invoker level from 5th to 8th (since he has 8 Hit Dice). This gives him access to Lesser Invocations, a total of 5 Known Invocations, and 4d6 Eldritch Blast Damage. If he later gained a fighter level, he would gain the remainder of the bonus and his warlock invoker level would become 9th (since he now has 9 Hit Dice), granting him an additional d6 of Eldritch Blast Damage to a total of 5d6.
Normal: Your Invoker level is equal to your warlock level (or any prestige class options that increase invoker level) to determine Eldritch Blast damage and the number/availability of Invocations.