This is a Monster — a class feature gained through that class's own talent choices, not a feat you pick through normal feat selection.
Choose one of your spell-like abilities, subject to the restrictions described in this feat. You can use the chosen spell-like ability as a scarring spell-like ability three times per day (or less, if the ability is normally usable only once or twice per day). When you use a scarring spell-like ability, a target that fails its saving throw against the spell-like ability takes a -2 penalty on saving throws against emotion and fear effects you create, and a -1 penalty on saving throws against other emotion and fear effects, for the next 24 hours. If the spell-like ability doesn't allow a saving throw, you can't choose to enhance it with this feat. Penalties from multiple scarring spell-like abilities don't stack. This feat can be applied only to spell-like abilities with the emotion or fear descriptor. You can only select a spell-like ability duplicating a spell with a level less than or equal to 1/2 your caster level (round down) - 1. For a summary, see Table 3-1 on p79. [Special] This feat can be taken multiple times. Each time it is taken, you can apply it to a different spell-like ability.
Prerequisites
Spell-like ability at caster level 4th or higher