Sudden Ability Focus

(Tome of Magic, page 74, DnD 3.5)

[General]

One of your special attacks becomes more potent than usual.

Prerequisite

Special attack

Benefit

Once per day, you can increase the save DC of any special ability you have — including the special abilities granted by a vestige — by 2. You can still use the Ability Focus feat normally if you have it, and the DC increases stack. You must declare the use of this feat before you use the ability. A continuous-use ability (such as a gaze attack) can benefit from this feat for only 1 round.

Special

This feat can be taken multiple times. Each time you take it, you can apply the Sudden Ability Focus feat one more time per day. You cannot apply Sudden Ability Focus more than once to a single use of a special ability.