Norn-Queens (also known as Splicer-Beasts) are the productive parts of the Tyranid swarm. They live upon massive Hive Ships in huge chambers at the centre of the Hive Fleet and ingest genetic materials, churning out all the countless types of creatures that make up the Tyranid Hive Fleet. All Tyranids have links back to a Norn-Queen, as the only way for Tyranids to reproduce is via this cloning technique. It is said that they lead the Tyranid forces and direct the evolution of the Tyranid race.
Norn-Queens require a constant supply of fuel, in the shape of genetic material, in order to reproduce or bring forth new Tyranid life forms. This mainly consists of the fluids formed in Reclamation Pools, that are pumped up into the Hive Ships through massive Capillary Towers. Genetic material is also supplied directly to the Norn-Queen via living creatures and scavengers, such as Coffin-Crawlers. All this, including transport creatures, is pumped into the great jaws that are located at the top of the Norn-Queen, and synthesized by the Queens genetic shredder organs. The dissembled DNA structures form a gene-bank, which provides the raw material from which new creatures are created. Once a type of bio-construct has been designed more identical creatures can be cloned by the Norn-Queens.
Norn-Queens are capable of bringing forth new bio-constructs in a variety of different ways, each designed to ensure maximum efficiency. Most bio-constructs are born as tiny wriggling larvae or may begin life as eggs that must be nurtured further before they hatch and develop into adults. Clusters of eggs spill from rows of ovipository orifices along its flanks, fluid filled depressions on its upper surface writhe with maggot-like larvae, fetal sacs hang like ripe fruit from umbilical branches, and huge larval Teleporter Worms burst from incubator pouches on the Norn-Queen's sides. Simpler bio-constructs may emerge already in their adult form to be gathered and directed by the horde of creatures that feed and serve the Norn-Queen.