Tyranid

In the fictional universe of Warhammer 40,000, the Tyranids are a race and a playable army in the tabletop miniatures wargame.

The Tyranids are aliens from outside the galaxy who have come to devour all life, one planet at a time. Though they collectively possess a powerful intelligence, they cannot be reasoned with. Tyranids come in diverse forms, each individual having been engineered to fulfill a specific role. All of their technology is biological, named in the Universe as biomorphs due to their components being alive.

Tyranids were first described in Rick Priestley's Rogue Trader, the first edition of the Warhammer 40,000. At that time they were not an emphasized race in the game, instead representing a limited number of occasionally encountered alien antagonists. Their physical appearance was not imposing or especially horrific: they were depicted as six limbed, relatively diminutive creatures (an appearance which would later be assigned to Tyranid termagants). In later iterations of Warhammer 40,000-related products (starting with the release of Advanced Space Crusade) the Tyranids were given a complete makeover and became a major race, popularized by a number of successful expansions. Unlike most Warhammer 40,000 races, the Tyranids do not have a direct Warhammer Fantasy Battle counterpart, but share a horde mentality with the Skaven and Lizardmen armies while bearing some resemblance to the latter through having somewhat reptilian features. This, along with the extensive use of larger, stronger creatures and primal defense mechanisms leads to the widely-drawn inference that the Tyranids are the closest Warhammer 40,000 counterpart to the Lizardmen.

Tyranids often form a fast-moving close-combat army that relies on overwhelming its enemies through waves and waves of mostly small but deadly creatures. They may also rely heavily on ranged combat, if different selections are made, or field an impressive but small array of monstrous titans rather than a typical swarm. Tyranid armies are therefore able to bring a varied threat to bear on their opponents.

Games Workshop has introduced three main hive fleets, called Behemoth, Kraken, and Leviathan. The most recent Codex has also introduced a number of smaller hive fleets and splinter fleets, such as Hydra and Gorgon, among a number of others, although the book primarily focuses on the three main fleets. It is noted that these names are given by the scholars of the Imperium, rather than the Tyranids themselves. In fact, there is no evidence in the fiction that Tyranids have language or civilization, at least not as understood by other species native to the Milky Way. In many stories, they communicate with a complex array of insectoid clicking and buzzing noises, as well as reptilian war cries, growls, and hissing sounds. Tyranids are thought to communicate primarily via a strong synaptic link to the so-called Hive Mind.

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