SPORE CHIMNEYS

File: 06843/b. Tyranid Spore Chimney.

These structures are formed by a rapidly growing mycetic colony that feeds off the dermis of the planet and leeches minerals from underlying strata to form the coral-like skeletal structure upon which the colony grows. Observations from functional satellites indicate that these may reach heights in excess of 350 metres, allowing spores from ripe polyps to reach long distances. They appear as dark cones with a hollow centre. Around this core is where the mature fungal colonies migrate to expel their spores. These are seen as large fist-sized taunt-skinned spheres. Rupturing when fully mature, they spread millions of spores into the wind.

Many pollinating insects feed on these huge spires and fan the spores into the air with their wings. Avian species are often drawn to the spires by the insects that are attracted to the fungus. In the process they are covered with a fine dust of spores and when they take flight again they spread the spores as well. Formation of these structures indicates a pervasive Tyranid infestation within the planetary biome.

These spores, produced and spread upon the atmospheric winds, have several roles within the Tyranoforming process. While generated by the same fungus, spores are multifunctional and serve in two distinct capacities. Like many Tyranid organisms, the situation dictates how the spores develop.

File: 06844/a. Accelerated vegetation growth due to Tyranid spores.

When in contact with flora of any type, the spores operate in a catalytic fashion. This serves to induce explosive growth and reproductive cycles, stimulating all the growth hormones within plants, thus increasing the cell division exponentially. Following each rain cycle, the spores cause thick, lush foliage to form on all nutrient-rich soils of the planet. Thick macro algae blooms appear within the oceans in all areas where sunlight penetrates the depths. The spores also form symbiotic relationships and infest the fruits of the plants in a manner similar to a virus, causing the progeny to exhibit the same enhanced growth cycles. This mechanism also stimulates the Tyranid plant life which are breaking down materials on the planet as well. In effect, the native plants leech the nutrients from the soil at an alarming rate hastened by the spores' actions. These plants are harvested by the Ripper swarms, but regrow quickly until all the essential minerals and nutrients have been extracted from the soil. Magma Vents (q.v.) help replenish the soils, as do the spores effect on the planet's animal life in Harvester mode.

In Harvester mode, necrotizing spores are highly dangerous to fauna and if inhaled will root within the pulmonary system of the animal, reproducing at an astounding rate and suffocating the creature in a short time. [Standard Class V Imperial respirators are sufficient for short term exposure to the spores, however lengthy exposure requires supplied air or active osmotic lung filtration systems.] The fungus continues to digest the body and growing, sending a deep taproot down into the ground before beginning to grow skyward. Thus hundreds or thousands of these smaller chimneys spread out from the initial source with each death, creating an ever-widening radius. The rate at which the plague spreads is dependent on the endemic resistance to the spores and the atmospheric volatility of the region but it progresses with exceptional speed upon many vectors.

Larger animals also facilitate the spreading of the spores by eating infested fruits or infected hosts, which then attack the host via the gastrointestinal tract. In this manner they initially act as catalytic spores and shift to harvester mechanisms once in contact with fauna. The spores have a peculiar effect on many migratory fauna, initiating the migratory response and thus spreading the infestation even further. The larger the animal and the slower its metabolism, the longer it takes for it to succumb to the infestation. Thus large herbivores tend to travel long distances before dying. Any scavengers that feast upon the corpse become infested with the more deadly pulmonary infection as well. Excessive thirst seems to be a symptom of the infection's final stages resulting in concentrations of chimneys around potable water sources, soon rendering them toxic due to algae and forcing infected animals to seek fresh supplies. This quite often leads them in desperation to reclamation pools where they are subdued and added to the harvested stores.

Tactical Dogma: Imperial forces that contact such structures should avoid any direct explosive or kinetic assaults upon the spire. Such attacks serve only to spread the fungus. Demolition of the spire will spread untold amounts of spores over a large area. Immolation is the best single method of dealing with the structures but Li6 Rad-Grenades produce short-term radiation of a Becquerel level capable of destroying the spores and all other life in a small area without any kinetic action dispersing spores further. Larger structures are best dealt with during the frequent rainstorms if these methods are insufficient due to size. The spores will be more contained and less of a threat during the rain.

RECLAMATION POOLS:

File: 06834/f Tyranid Reclamation Pool.

Exceptionally dangerous features of the Tyranoforming of a planet are the reclamation pools that render down slain animals as well as those Tyranids that have lived out their useful life, are injured or are dead. The cocktail of enzymes, acids, viruses and catalytic agents present in this deadly morass can destroy nearly any known material and should be viewed with the utmost caution. The depression where the pool itself resides is lined with a thick, viscous living carpet of macro-algae. Utilising an unknown mechanism <based on examination of other Tyranid weapons systems it is likely that an inert lipid layer is responsible> to prevent itself from being dissolved by the solution, it contains the pool. These pools generally begin to take form in natural depressions housed between native watersheds during the early days of the Tyranid infestation. As the harvesting process increases exponentially during the event, they will become unable to contain the amounts of harvested materials once all mechanisms are integrated and functional. At this point we begin to see Capillary Tubes <q.v.> forming to remove materials from the pools on a constant basis.

The pool itself is home to amorphous protoplasmic organisms of exceptional size. These creatures are the only mobile creatures, even within the Tyranid horde, that can withstand the chemicals within for extended periods of time. They carry the fallen and injured Tyranids into the pool as well as any large creatures that die in close proximity. They appear to act as guardians to the fragile pool system, making certain its epithelium is healthy and that the connections to the capillary tubes remain open. They will also attack by spraying materials from the pool at any non-Tyranid creatures that venture too near. Some Tyranids also seem to have an internal bio-clock that regulates their effective operational time, as on several occasions apparently healthy Tyranids have been observed entering a reclamation pool under their own power. It is unknown if pheromone influences are at work to suppress the creatures' innate self-preservation instinct or if the hive mind is able to effectively stifle this entirely when required, though the latter seems a likely assumption from the evidence. All attempts to isolate and replicate the morass or cultivate the macro-algae have met with failure to this date. But it remains promising that the Tyranids may be susceptible to effective chemical warfare if we can isolate the mechanism by which this material or the bio-clock operates. These pools are utilised in differing ways by each hive fleet.

During the final stages of Tyranoforming the pools become unimaginably massive, becoming oceans and lakes themselves with hundreds or thousands of capillary towers operating in them. At this juncture little if any of the indigenous life exists on the planets' surface. The reason that oceanic basins are not used for this accumulation appears a mystery. Perhaps the need for direct sunlight or some pressure requirement prevents it. However we can only really speculate as to how the mechanisms are utilised in the deep oceans.

Additional Harvesting: Most fleets reclaim the materials from Rippers which return from gorging themselves on the planet's resources by dissolving the Rippers themselves within these pools. However, more evolved fleets save biogenesis energies by having the Rippers simply regurgitate the digested materials before going out to forage again. The gullets of these Rippers contain the same macro algae as the lining of the pools, enabling them to digest nearly anything. This nutrient broth is the lifeblood of the hive fleet providing nearly all the sustenance for the massive hive ships. Disruption of this harvesting is critical to thwarting any Tyranid exploitation of a planet.

TYRANID MAGMA VENTS:

This is another of the features often encountered when dealing with Tyranid infested biomes. These vitrified tubes are bored down past the Mohorovicic Discontinuity (between the crust and mantle) to allow gases trapped deep within the planet to escape into the atmosphere. Sulphur dioxide, carbon dioxide and other gases escape in superheated plumes from these shafts which are typically situated upon or near tectonic plate junctures. Periodic eruptions of steam from these vents are typical and a hazard to unprotected personnel. This is more common in those vents located far from tectonic fault lines. This affects the planetary climate aiding other Tyranid methodologies in the harvesting of resources. Vents bored within the oceanic basins slowly warm the oceans increasing the climatic catalyst effect even further. Induced volcanic eruptions sometimes result if the area is sufficiently unstable.

Magma Corers, large creatures that appear to be related to the Carnifex, dig and dissolve their way through the sedimentary and igneous rocks down to the mantle and the magma. <No specimens of this creature have yet been procured for study by the station, so detailed analysis of biological countermeasures to extremes of temperature are speculative at this time.> The residual minerals exhibit molecular disruption similar to that found on Tyran. Presumably these creatures utilise some psychic matter-manipulation or agitation to facilitate this amazing feat. As they tunnel, they secrete a vitrifying gel which coats the tube and prevents its collapse until the tap is deep enough to begin expelling the compressed gases. In areas where magma is sufficiently caustic, the low viscosity lava will typically erupt releasing huge quantities of dissolved gases. In areas where the lava is acidic and viscous, explosive eruptions and pyroclastic flows have occurred. This results in significant loss of life to all indigenous creatures within miles of the occurrence. Some Tyranid creatures could survive around the periphery of the blast and gas cloud but the intense heat is sufficient to cause the demise of any caught within the cloud. It is unknown if the Magma Corers survive once they reach the 35-40 km depth at which this process is initiated. The tenacity of Tyranid creatures is remarkable but none should be capable of surviving such conditions; it would seem to be suicidal even for such creatures. The ability of the Tyranids to breed a creature whose sole <known> purpose results in its death is quite astounding. Magma vents are also utilised as a geothermal energy source for the <q.v.> Tyranid broodhive complexes. Dozens of these types of vents are utilised to heat the entire hive and provide thermal energy to incubating broods. They sometimes appear to bore vents below the larger regional spore chimneys to provide a draught within the structures.

CAPILLARY TOWERS:

File: 06973/g Capillary Tower.

File: 06973/h Destoyed Capillary Tower.

Huge living towers which stretch high into the thermosphere. Composed of a crystalline exoskeleton system with inconceivable structural integrity containing the singular huge rope-like creature. These creatures perform a remarkable feat by moving gathered material from the reclamation pools up to near orbit by use of somatic methods alone. Connected by miles upon miles of subterranean tubes, one capillary tube can serve all the pools in an area within a 50 km radius. These creatures only appear in the final stages of the Tyranoforming of a planet and subsequently have not been examined in detail. The towers move huge quantities vertically by use of chambered somatic cells with intricate valve systems. Since the weight of such a huge column of material would be too stressful for any valve to withstand, the towers utilise an undulating oesophageal method. In this way the reticulated musculature need only support the weight of each individual bolus rather than the mass of a continuous column. Hive ships reach down into the upper atmosphere of the planet to attach themselves to these structures using huge umbilical cords. Waning planets bristle with these structures as the hive fleet clusters nearer and nearer the planet, removing the oceans and atmosphere before departing to seek more prey. As the atmosphere wanes and the seas dry up, the great worms of the towers begin leaching the most vital nutrients from the towers themselves. Without the wind and surf to batter them they require less and less structural support. By the time the creatures retract up to the hive ships, their towers are so fragile that they collapse, leaving miles of rubble strewn across the battered landscape, similar to that found on Tyran.

BROODHIVES:

These huge structures are an amalgam of many other types of Tyranid buildings. They resemble, more than anything, a huge earthen mound, with spires thrusting skyward emitting thick plumes of dark smoke. The smoke is in fact spores forced out the chimneys of the hive by geothermal draughts created by magma vents deep within the hive. These magma vents do not go quite as deep as those outside the hives and are filled with ground water and Tyranid secretions to create a hot and humid environment. Within this dark, damp and hot system the broods incubate quickly and go forth to devour the planet's resources. Thousands upon thousands of Rippers endlessly ravage the planet, returning to deposit their harvest into the sheltered reclamation pools. Capillary towers have also been seen connected to the highest levels of these monolithic structures. Based on the few assaults launched against such structures, they mimic the insides of the hulking hive ships, including many unseen dangers and are filled with ravenous Tyranids which are quite active and aggressive. Not all Tyranid infestations result in the formation of these structures. They actually appear to be an aberration. Conjecture has it that these may form when an unsupported Tyranid infestation is taking place. That is, a small number of Tyranids in a location without the benefit of a global assault. Perhaps this is analogous to many insect species that form new colonies by a small faction breaking off and moving to colonise elsewhere.

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