The Harpy is the swarm's master of the skies, a winged monster far larger and more dangerous than the Gargoyle broods it often flies among, roughly the aerial equal of a Trygon. It sweeps across the battlefield on great membranous wings, its limbs bearing an array of symbiotic weaponry that commonly includes a stranglethorn cannon or a heavy venom cannon alongside its rending talons.
Slung beneath its abdomen hang bulging cysts that gestate clusters of spore mines, and as the Harpy passes over an enemy formation it releases this living payload to drift down among them and detonate. Lightly built for the sake of speed, it disdains the sustained dogfight in favour of savage strafing runs, sweeping in to loose its weapons and scatter its bomblets before climbing away beyond easy retaliation.
The beast takes its name from the piercing shriek it can unleash, a sonic assault powerful enough to stun and even wound those caught beneath it. Between its guns, its spores and its screaming dives, the Harpy comes to dominate the airspace over a prey world, clearing the skies of resistance so that the swarm below may feed unmolested.