Shaped Splash

 
Prerequisite(s): Halfling, Dex 13+, Base Attack Bonus 1+
 
Benefit: If you throw a splash weapon and it hits the creature you targeted, you can immediately make an attack against any adjacent creature to the first. If the second attack hits, the secondary target takes full damage from the splash also. In addition, you can choose not to deal splash damage to specified creatures adjacent to the targets. If your initial attack fails, determine location of the slash as normal.
 
Source: Races of Eberron