Tervigon

The Tervigon is a wonder and a horror of Tyranid bio-engineering, a vast creature that serves the swarm as a self-propelled nursery. Beneath its lumpen, heaving carapace it carries dozens of Termagants in dormant slumber, and at need it births them in fresh broods, disgorging living reinforcements onto the battlefield in a ceaseless, glistening tide.

This makes the Tervigon a strategic nightmare for any defender. Held to the rear of an assault, it steadily replenishes the numberless gaunt broods that do the swarm's dying, so that a line which seems on the verge of being overrun and cleared is suddenly flooded anew. Every Termagant cut down is merely one more that the Tervigon can replace, and the grim arithmetic of attrition tilts ever further in the swarm's favour.

It is also a powerful synapse creature, its mind a strong node in the Hive Mind's web. Aboard the fleet's bio-ships the Tervigon does not lapse into the deep dormancy that claims other organisms; instead it prowls the living corridors as a guardian, spawning gaunts to delay any intruder and using its synaptic strength to rouse slumbering monsters to the defence. It is at once the swarm's mother and its warden.