Swarm Exile Shirren

While most shirrens broke away from the Swarm long ago, you're a more recent convert. You come from a group of castaways that have more in common with the Swarm than most other shirrens. You gain a bio-cannon ranged unarmed attack with a range increment of 20 feet that deals 1d6 acid damage. Your bio-cannon is in the corrosive weapon group. When you select this heritage, choose whether this attack comes from an underslung launcher on one of your arms, a launcher mounted over one of your shoulders, or from your mouth. You can't change this selection.