Patient Hunter
Faction Pack v1.2 reprints this rule verbatim, so the wording is first-party. During the third, fourth and fifth battle rounds, ranged weapons equipped by T'AU EMPIRE models from your army have the [SUSTAINED HITS 1] ability. During those same rounds, while a unit is a Guided unit, each time a ranged attack is made by a model in that unit that targets a Spotted unit, you can ignore any or all modifiers to that attack's Ballistic Skill characteristic and/or all modifiers to the Hit roll. Two corrections to what is usually written about this detachment: there are no re-rolls anywhere in it, and the second clause is a modifier-ignoring clause rather than an accuracy bonus, so it is worth most against armies that stack negative modifiers on you and worth nothing against an opponent who applies none.