As we have both known the Terran Firebats have splash damage and special bonus damage property.Here the bonus damage means ;they give extra harm against some type of units,like Vultures.The firebats are not widely used but at some conditions the role of the Firebat becomes very important.For example if the enemy has large amount of Zealots or Zerglings the usage of few firebats completely will turn the war destiny into your advantage.But here the number must not be too much it must be at optimum amount.In 2v2 or 3v3 games the Firebat usage needs extra care because the splash damage may harm your allies.If you want to help your ally especially drones/probes you can give more harm to your enemy than the enemy do not use firebats at the ally resource site.Firebat drop can be used to reduce enemy economics but you must supply the firebats with medics to longer your micro army lifetime.Firebat army needs always good micro and interest.