Tyranids

"They come from between the stars, a god of hunger made flesh, to harvest the galaxy of life."

- -- Inquisitorial Xenologist, Darnye Gotopo

The Tyranids are the most alien of the races to infest Imperial space, for they come from beyond. Their hive fleets stretch out like tendrils, great chitinous bio-ships drifting in brooding silence. Once the remorseless shoals of the bioships detect the presence of a prey world, they close upon their target, grasping it like some many-tentacled beast seizing its food. In the ensuing invasion, the world will be consumed, for the Tyranids hunger for all living matter. There is no escape from this final embrace and when the Tyranids finally depart, they leave behind a barren world, a scoured ball of rock now devoid of anything that lives. A Tyranid hive fleet consists of millions of living starcraft, each home to untold numbers of monstrosities evolved from the geno-organs of the ship's reproductive chambers. All the creatures serve the entity that is the ship, and the ship exists only as part of the horrific super-organism that is the fleet. Even when dead, organic matter is reconstituted back into the ship, along with captured biomass from the invaded planet. It is then all dissolved into a rich biological gruel used to make new Tyranid creatures, each ready to serve the Hive Mind and begin the feeding process anew. But on Gladius, the Tyranids are few and scattered, brought here by meddling men. The warp storms keep them distant from the will of the Hive Mind and the Imperial citizens think of them merely as pests. They should worry more...

Features
The Great Devourer
 * Initial Challenge: Hard
 * Biomass: Food and ore resources are replaced by a single biomass resource.
 * No Energy: Influence is used for building maintenance
 * The Ravening Swarm: Cities are more restricted in size, but less penalized by quantity.
 * Reclamation: Production buildings can reclaim units to regain biomass and production.
 * Feed Upon The Planet: Cities and Malanthropes consume tile biomass and strip the ground down to bedrock.
 * Prey Adaptation: By defeating and consuming enemies, Tyranids evolve better ways of beating them next time. Enemies defeated in the area of a Malanthrope generate research points.
 * Instinctive Behaviour: Units outside the range of a synapse creature revert to their instinctive behaviour until contact is re-established. Whilst in range of a synapse link, units are immune to morale effects. The Hive mind's attention can be focused to temporarily override a unit's instinctive behaviour.
 * Poisoned Weapons: Many weapons do additional damage against infantry units.
 * Acid Blood: Many monstrous creatures cause melee attackers to take damage.