Cleave

Prerequisites: proficiency in a heavy martial weapon

You gain the ability to cleave enemies around you with a heavy martial weapon, but at the cost of 1/5 of your movement speed per enemy cleaved.

Before you attack a creature with your action, you can use your bonus action to add a number of additional creatures to that attack. The additional creatures must be adjacent to you, within your reach, and the attack must cleave the creatures one into the next. Roll to hit and use the same attack and damage rolls for each creature.