Editing Warhammer 40,000 (section)

===Tyranids===
{{redirect|Tyrannids|the bird family Tyrannidae|Tyrant flycatcher}}
[[File:WH40K Tyranid Warrior.jpg|left|thumb|A Tyranid warrior]]
The Tyranids are a mysterious alien race from another galaxy. They migrate from planet to planet, devouring all life in their path. Tyranids are linked by a psychic [[Group mind (science fiction)|hive mind]] and individual Tyranids become feral when separated from it. Tyranid "technology" is entirely biological, all ships and weapons being purpose-bred living creatures.

Tyranids have a preference for melee combat. Their infantry models tend to be numerous and fast but frail. They have low point costs, meaning Tyranid armies in the game are relatively large (many cheap weak models, as opposed to armies with few expensive powerful models such as the [[Space Marine (Warhammer 40,000)|Space Marines]]). Tyranids also have the most powerful countermeasure against Battleshock called Synapse. The Synaptic network is an aura around powerful leader beasts that compels Tyranids to fight on.<ref>''Warhammer 40,000: Index: Xenos 2'' p 85</ref>

There is a sub-species of the Tyranid race called "genestealers".<ref>''White Dwarf'' #114 (1989), pp. 31–36</ref> When a human is infected by a genestealer, they are psychically enslaved and will sire children who are human-genestealer hybrids. These hybrids will form a [[secret society]] known as a genestealer cult within their host human society, steadily expanding their numbers and political influence. When a Tyranid fleet approaches their planet, they will launch an uprising to weaken the planet's defences so that the Tyranids may more easily conquer it and consume its biomass.

In earlier editions of the game, Genestealer Cults could only be used as auxiliaries to a regular Tyranid army, but since 8th edition, they can be played as a separate army. Although there is a dedicated line of Genestealer Cult models, a player can also use models from the Imperial Guard (a sub-faction of the Imperium) in their Genestealer Cult army. This is an exception to the common-faction rule and is based on the logic that these "human" models are actually genestealer hybrids who look perfectly human. Like other Tyranids, Genestealers are fast and hard-hitting but fragile. All Genestealer Cult infantry and bikers have a trait called "Cult Ambush" that allows them to start the match off table and later be set up on the table, instead of being set up in the designated starting zones at the start of the game (similar to the Space Marines' "Deep Strike" ability).

The visual design of the Tyranids was inspired by the art of [[H. R. Giger]], with the genestealer sub-race being further inspired by the [[Alien (creature in Alien franchise)|Xenomorphs]] from the [[Alien (franchise)|''Alien'' franchise]].<ref>{{Cite book|title=Zones of Control: Perspectives on Wargaming|last=Harrigan|first=Pat|others=Kirschenbaum, Matthew G.|year=2016|isbn=9780262334945|location=Cambridge, Massachusetts|pages=608–611|oclc=947837974}}</ref>