Your allies need not fear friendly fire.
BENEFIT
When casting a selective spell with an area effect and a duration of instantaneous, you can choose a number of targets in the area equal to the ability score modifier used to determine bonus spells of the same type (Charisma for bards, dark knights, holy knights, illusionists, necromancers, red mages, and summoners; Intelligence for black mages and blue mages; Wisdom for geomancers and white mages). These targets are excluded from the effects of your spell. Spells that do not have an area of effect or a duration of instantaneous do not benefit from this feat.
MP Increase: +1 (a selective spell costs 1 additional MP more than the actual MP cost of the spell.)