leg wound

It was truly rare to corner such a creature alone, and that gave the squad an equally rare opportunity to kill it. Cassius ran at it, holding his fire, and brought his crozius down in a crushing overhead blow.
It would have done no good to strike at its torso or head. What the lightning-quick boneswords did not parry, the layers of chitin would turn aside. Instead Cassius aimed low, at the muscle and exoskeleton of the Swarmlord's upper back leg.
With a burst of light, the armour of its thigh was torn open. Hard shrapnel pinged against Cassius' armour. The muscle packing the Swarmlord's leg was laid gorily open and the monster howled.

Space Marine Legends: Cassius