Heighten Spell-like ability
( Complete Arcane, p. 80)[General]
You can use a spell-like ability as if it were a higher spell-level equivalent than it actually is.
Prerequisite
Spell-like ability at caster level 6th or higher,
Benefit
Choose one of your spell-like abilities (subject to the restrictions below) to use at a heightened level up to three times per day (or the ability's normal use limit, whichever is less). The spell-level equivalent of the heightened spell-like ability is two higher than its normal level (to a maximum of 9th level), with all effects dependent on spell level (including saving throw DCs) calculated at the higher level. The spell-like ability you wish to heighten can be chosen only from those abilities that duplicate a spell of a level less than or equal to 1/2 your caster level (round down), minus 2. For a summary, see the Caster Level to Empower column in the table on page 304 of the Monster Manual.
Special
This feat can be taken multiple times. Each time, you apply it to a different one of your spell-like abilities.