Path Of Exile: Ascendancy is launching on next Friday, one of the new skills to be in Ascendancy is Sunder. Sunder is a ranged melee skill that can only be used with Maces, Staves and Axes.
Striking the ground with Sunder causes a chasm to shoot forward, damaging all enemies in its path. Every enemy that is hit releases an additional shockwave, damaging all foes around them. Against a cluster of enemies, these overlapping shockwaves can be devastating.