Cleave

Prerequisite: Great Weapon Combat Style

You can strike two adjacent foes with a single swing. Once per round, when you make a melee attack with a heavy weapon that reduces a creature to 0 hit points, any excess damage from that attack may carry over to another creature nearby. You may target another creature within 10 feet of your original target and within reach of your weapon. If the original attack roll can hit it, apply the remaining damage to it.