Timeline of the Warhammer 40,000 Universe

''This is an article about the fictional setting of the Warhammer 40,000 games systems and their derivatives. For a discussion of the games systems themselves, please refer to Warhammer 40,000.''

This article relates to events in the universe prior to the late 41st Millennium in the Warhammer 40,000 setting. Throughout this article, comparative references to dates will be with respect to the approximate decade 990.M41 - 999.M41. This is the time period in which the perspectives of the Imperium and the Eldar are particularly relevant and it represents the in-game present.

Pre-History
The Old Ones

The Old Ones are an incredibly ancient sentient race of the Milky Way Galaxy, pre-dating all other known intelligent beings. The Old Ones are commonly thought to have been an advanced, reptilian race whose civilization reached its height in excess of sixty million years ago. The Old Ones were responsible for the creation or genetic advancement of most of the currently active intelligent species of the galaxy, including the Eldar, the Krork (Ork precursors), the Slann and the Jokaero. The Old Ones were potent psychics who routinely used the powers of the Warp for a wide variety of technological applications. The Old Ones constructed a system of instantaneous faster-than-light portals through Warpspace that were very similar to the Eldar's Webway (and was probably its more advanced precursor). These portals connected all of the Old Ones' colony worlds across vast swathes of interstellar space.

The War in Heaven

Eventually, a great conflict later known to the Eldar as the War in Heaven arose between the C'tan, immensely powerful, incorporeal beings composed of pure energy who existed solely within the material universe, and the Old Ones. The Old Ones, being physically weak and few in number but mighty in intellect, technology and psychic ability, first created the psychically powerful Eldar race to serve as their front-line soldiers against the servants of the C'tan and stimulated the genesis of the Eldar's gods within the Warp as beings who fought alongside their mortal charges. In response, the C'tan enslaved the Necrontyr race, ancient but ineffectual enemies of the Old Ones, by bonding them within armoured shells made from a form of "living metal" called necrodermis. The Necrontyr thereafter became known as the Necrons. The Necrons then fashioned for their C'tan "Star Gods" corporeal avatars made of necrodermis so that the C'tan could more easily interact with the physical world and take the conflict to the Eldar and the Old Ones. The C'tan directed their now-soulless Necron slaves to conduct "red harvests" of all intelligent life in the galaxy as the C'tan discovered that feeding on the life energies of intelligent beings was far preferable to the stale diet of solar energy that was their native source of sustenance. In response to the Necron threat, the Old Ones created other servant races to act as "biological weapons," including the Krork who eventually devolved into the brutal and dangerous Ork species. But in time the Necrons proved all too successful and the Old Ones were rendered extinct. The constant use of psychic powers by the Eldar and the Old Ones also drew the attention of the Warp entities known as the Enslavers, who flooded into the material universe and began to kill off much of the intelligent life in the galaxy. Between the onset of this Enslaver Plague and the success of the Necrons' "red harvests," the population of intelligent life in the galaxy plummeted drastically some sixty million years ago. Confronted with potential starvation or a return to their bland solar diets, the C'tan were forced to withdraw into hibernation, hiding for many millions of years while their Necrons slept on forgotten "Tomb Worlds" inside massive pyramidal complexes, tended by artificial robotic constructs. There they waited for long millennia until the galaxy was once more repopulated with sentient beings. The Necrons and C'tan were reawakened in the 41st Millennium by the human race's explorations, in spite of warnings from the Eldar about their ancient enemies that came far too late.

The Human Ascendancy
The Stellar Exodus

The Stellar Exodus is a poorly-understood period of human history which is generally accepted to cover the majority of mankind's initial forays into interstellar space and the genesis of most of the oldest human colonies. This period is generally understood to lead into the Dark Age of Technology sometime around the 15th Millennium. During much of the Stellar Exodus, humanity lacked any knowledge of the existence of the Warp or Warp drive and so was forced to travel between the stars in great sublight generation ships or using cryogenic hibernation.

Dark Age of Technology

Again much of this era of human history that lasted between approximately the 15th Millennium and the 25th Millennium is mysterious. It was in this time that the psychic mutants called Navigators were first born, and combined with the invention of the Warp drive, allowed humanity to travel between worlds faster than the speed of light. The existence of rapid interstellar travel allowed human colony worlds to interact on anirmal timescale for the first time and interstellar commerce and communication became possible, allowing like-minded human worlds to join into political and economic combines for their mutual benefit. Eventually, at some point during this era, all of humanity was united beneath some form of federated interstellar government. What is also known (largely from the works of Keeper Cripias) is that a group known as the Golden Men relied on the works of the Stone Men in order to create a fantastically prosperous interstellar society, but one devoid (by later Imperial standards) of spirituality or piety, focused instead upon the advancement of science. The Stone Men are known to have created a third group, the Iron Men, postulated to be some form of artificially intelligent robots, in order to assist them in their labors and carry out military duties. The Iron Men became uncontrolled and rebelled against their human creators, and a cataclysmic conflict broke out, resulting in a partial Malthusian Catastrophe across much of the settled galaxy. Even worse, following the destruction caused by the war against the Iron Men, human psykers began to appear in large numbers across many human colony worlds, one of the harbingers of the final decline of the Eldar empire which controlled even more of the galaxy than mankind did in these years. The result was humanity's first introduction to the daemonic horrors of the Warp and the ultimate collapse of human interstellar civilization during what became known as the Age of Strife.

The Age of Strife

During the so-called "Dark Age of Technology," humanity had reached its scientific and technological peak. The "Standard Template Construct", or STC, a database of schematics for all known advanced human technologies, had been perfected by human scientists and engineers and allowed an unprecedented expansion of humanity throughout the galaxy.

One of the reasons humanity was so successful at conquering a large part of the galaxy was the development of the artificial constructs now only known as the "Iron Men". These powerful and fully intelligent combat robots won many wars for humanity, but for some reason turned against their masters at the end of the Dark Age of Technology. The war was eventually won by humanity, but at a great cost. The damage was catastrophic and had shattered much of humanity's power. Unfortunately, this was only the beginning of mankind's misfortunes.

As humanity became widely dispersed across the galaxy during the Age of Technology, the ancient Eldar empire began its decline; the great success of the advanced Eldar race had led to decadence and hedonism on a grand scale. Within the immaterial, psychic universe of the Warp, the spiritual corruption of the Eldar civilization was reflected in the forming of a new Chaos God, Slaanesh, which in turn caused massive disturbances in the Warp; parts of the galaxy became isolated by these Warp storms, making Warp travel and interstellar communication increasingly impossible as the years passed, cutting off many human colony worlds from one another, including those of the Solar System.

Towards the end of the Age of Technology psykers first appeared among humanity. While persecuted on many backwards, regressive human worlds as witches, in enlightened and progressive societies these psykers were at first protected and accepted. The initial intolerance for psykers would later seem prescient, as many human worlds fell to the dominance of daemons and other Warp creatures using possessed psykers as gateways into the physical world. Only worlds which had rigorously suppressed psykers survived the Age of Strife.

The Age of Strife followed the Age of Technology, as human civilisation collapsed in widespread insanity, daemonic possession, anarchy and inter-human civil war. Terrible weapons of the golden age of technology were unleashed, devastating many human colonies and turning once-verdant worlds such as Baal Secundus into irradiated desert planets. Many isolated and vulnerable human-colonized worlds also became prey to hostile alien races, such as the Orks.

In a relatively short span of time, the once galaxy-spanning human civilization was brought to its knees, and was forced to endure nearly five millennia of anarchy, terror, war, genocide and slavery. Other than tales of great suffering, little information concerning these long years survived this dark time to be known to the men and women of the Imperium.

The Fall of the Eldar
Before the Fall of their potent interstellar empire, the Eldar were a technologically and psychically advanced humanoid species, generally considered the most powerful race in the entire galaxy. Their technology had advanced so far that little or no labor was required by individual Eldar to provide the daily necessities of life, and as a result, at some point around the 24th or 25th Millennium, groups of Eldar began forming pleasure cults dedicated to the pursuit of experiencing everything that life had to offer.

Despite the prediction of the reclusive Eldar Seers that warned of impending doom if the Eldar did not change their hedonistic ways, government within the Eldar empire soon collapsed and the moral degeneration of their homeworlds and various colony worlds continued unimpeded. As the pursuit of ever more extreme experiences reached its height, death reigned in the streets of Eldar cities, hunter and hunted each being part of a twisted ritual of destruction which consumed millions. Some Eldar were able to see that their now-corrupt society was destroying itself, and fled in disgust; these refugees would settle in the distant, rural colonies of their empire, and would later be known as the Exodites.

Upon dying, the soul of all deceased, sentient beings traverse the bounds of the physical realm and go to rest within the Warp. As more and more corrupt Eldar died, their souls began to coalesce into a larger entity within the Warp, a living representation of the corruption that had taken their lives. This growing presence in the Warp caused massive Warp storms to aggregate across the galaxy, eventually making interstellar travel and communications impossible for the colonies of humanity, bringing on the Age of Strife. This collection of corrupt Eldar souls gained sentience sometime in the early 30th Millennium, creating the being known as the Chaos God Slaanesh, the Prince of Pleasure. When Slaanesh came to be, an ethereal explosion occured that spanned the extent of Warpspace within the Milky Way Galaxy, with the epicentre being the Eldar homeworlds. All Eldar caught in the immense psychic blast were instantly killed, their souls consumed by Slaanesh. Most of the remaining Eldar gods who existed within the Warp were destroyed by Slaanesh. Kaela Mensha Khaine, the Eldar god of war, attempted to combat the new Chaos God, but Khaine's form was shattered and exiled to the mortal realm where it came to rest in the Infinity Circuits of the Eldar Craftworlds but could be embodied in the form of animated statues called "Avatars", which rested in the hearts of the various Craftworlds during times of grave peril. The other Eldar gods to survive the Fall were the trickster god Cegorach (also called the Laughing God), who hid himself within the Eldar Webway, and Isha, who was ripped from the jaws of Slaanesh by the Chaos God Nurgle, who now keeps her as a slave.

The Fall utterly destroyed the once vast interstellar Eldar empire, leaving scattered bands of Eldar fighting for survival. Before the Fall, vast spacecraft called Craftworlds were constructed, enabling those wishing to escape the degeneration of the Eldar homeworlds to flee, along with samples of their lost worlds' flora and fauna. When the Fall occurred, the various Craftworlds rode out the ethereal shockwave in the Warp, some being destroyed in the process. The Exodite worlds, far from the epicentre of the terrible catastrophe, were largely untouched by the birth-scream of Slaanesh. In order to prevent the events of the Fall from ever recurring, the Eldar devised the Path system, by which every Eldar would follow a strict, almost fanatical life path pursuing a specific activity, such as crafting or war, for a portion of their long lifespans, before switching to another Path when the previous one grew stale. In this way, the Eldar hoped to control the extreme emotional and psychic sensitivity that had left them open to corruption by Chaos in the first place. However, some corrupted Eldar did survive the birth of Slaanesh by taking refuge within the Webway itself. These sadistic beings became known as the Dark Eldar, and they later preyed on humans and Eldar alike to find souls they coukld devour to keep their own lives from being consumed by Slaanesh.

The Great Crusade
The Great Crusade began as the Age of Strife came to an end for humanity. The Warp storms isolating human worlds had finally disappeared with the borth of Slaanesh and the Fall of the Eldar, and the Emperor of Mankind, who had united Terra under his rule during the Unifications Wars of the Age of Strife, was ready with his genetically-enhanced Space Marines and the Imperial Army to reunite all of humanity. Making a pact with the Priesthood of the Machine God on Mars, the Emperor promised to spare their lives (the Emperor despised their use of bionics and rigid adherence to organized religion as being against everything that he stood for) so long as they aided him in his mission to reunite humanity across the galaxy. The Emperor was a man of science and technology, and so in him many members of the Cult of the Machine saw the coming of the Omnissiah that had been prophecised. The Mechanicum of Mars pledged their support to the creation of a new Imperium of Man, and the symbol of the Imperium changed from the lightning bolt used by the Emperor during the Unifications Wars on Terra to the double-headed eagle known as the Aquila, to symbolise the union of the empires of Earth and Mars. With the forge factories and industrial output of Mars, the Emperor was able to refit his armies, and more importantly, he now had the use of the Mechanicus' Titan Legions, giant robotic war machines with the potential to dominate the battlefield.

At first, the Imperium's expansion into interstellar space was slow, since the Imperial Army was still small, and more importantly the Emperor's 20 Space Marine Legions were inhibited by the absence of their Primarchs, which made the enhancement time for the creation of a new Space Marine much longer. However, this was to end, as on Cthonia, a planet in a star system not far from Terra, the Emperor for the first time was reunited with one of his missing Primarchs, Horus. Having been discovered at an early age, the Emperor took Horus under his wing and taught him all he knew. Horus and the Emperor had a truly unique bond, that of father and son, and many times they saved each others' lives. But after 30 years, the Emperor discovered another of the Space Marine Primarchs, Roboute Guilliman. Although Horus was pleased at the discovery of one of his brothers, he secretly hoped to always be the Emperor's favorite son.

In time, all the Primarchs were found on the worlds they had been sent to by the machinations of the Ruinous Powers of Chaos, and each was placed in command of their respective Space Marine Legions. The Legions as a result were massively expanded with new recruits from their Primarch's adopted homeworlds, and new Space Marines could now be produced within only a single Terran year. But this acceleration produced fundamental defects within the psyche of each Space Marine which was later to prove fatal to many.

After the Imperial campaign on the world of Ullanor concluded upon bringing that planet into "Imperial Compliance," the Emperor claimed it as the greatest victory of the Imperium to date, and that Horus should be given all credit. Hailing Horus and his Luna Wolves Legion (later renamed the Sons of Horus), the Emperor stated that he would have to leave the expeditionary fleets behind and return to Terra to begin the next, secret phase of his plan to ensure humanity's domination of the galaxy, and that in his place Horus would be declared Warmaster, the de facto commander of all the Emperor's armies on the Great Crusade. Although Horus was troubled that the Emperor should leave him and his brother Primarchs to carry on alone for some unknown reason, with Horus as their new commander, the Imperium's armies and Space Marines continued to expand ever outwards, rediscovering lost human worlds and bringing them into the enlightened Imperium's fold. This situation lasted until the outbreak of the terrible Horus Heresy.

The Horus Heresy
Eventually, the Imperial Warmaster Horus fell to the temptations of the Ruinous Powers of Chaos and attempted to destroy the Imperium from within by usurping the power of the Emperor. The treason of Horus spread to embrace around half of the Imperium's military forces, from small planetary defence forces, right up to nine Space Marine Legions and several of the Adeptus Mechanicus' potent Titan Legions. The terrible civil war culminated in a massive seige of the Imperial Palace on Terra. After 55 days of fighting, the war was ended by the Emperor and Horus dueling in single combat aboard Horus' flagship in orbit of Terra. Although mortally wounded, the Emperor was able to strike down Horus. The Chaos Space Marine Legions and their allies retreated to the Eye of Terror, and the crippled body of the Emperor was installed into the 'Golden Throne'.

The Age of the Imperium
The Age of the Imperium is the setting for most of the works of fiction that describe the Warhammer 40,000 universe, and is typically referred to in the present tense. The approximate time period begins in the 31st Millennium, and continues as Games Workshop continues to release additions to the game. The Age of the Imperium is generally conveyed as spanning from the end of the Horus Heresy to the narrative present - a space of approximately ten thousand Terran standard years.

The Birth of the Imperium (M31)
In the immediate aftermath of the Horus Heresy, the Imperium underwent a massive structural reform in organisation to minimise the risk of future catastrophes. In the absence of the Emperor, power was shifted to the High Lords of Terra, and the Imperial Army was split up into the Imperial Guard and the Imperial Navy. The Inquisition was also formed during this time. The Space marines also underwent structural reform under the guidance of Roboute Guilliman, the main change being the Legions being split into one thousand man strong chapters. The structure of the imperium has since remained in this state.

The Age of Apostasy (M36)
The Age of Apostasy is another era of Imperial civil war and is considered to be one of the bloodiest eras of the Imperium's history after the Horus Heresy. An insane tyrant, High Lord Goge Vandire, became both Ecclesiarch and High Lord of the Administratum through bribery, blackmail, coercion and murder. Vandire started an period of time known as the Reign of Blood where multiple wars of faith were fought as Vandire attempted to gain control of the Imperium. The Reign of Blood lasted for 70 years before a messenger delivered the news that heralded its end. On the world of Dimmamar, a man named Sebastian Thor and his sect, the Confederation of Light, denounced Hgh Lord Vandire as a traitor to the Emperor. As an accomplished orator, Thor was able to sway billions to his cause. Eventually Vandire was besieged on Terra by several Space Marine Chapters, and several Imperial Guard Regiments. The Space Marines' fleet unleashed a massive orbital bombardment which caught most of the traitors in the open. Lord Vandire was killed by his bodyguards, the Brides of the Emperor, who were convinced that they had been tricked into betraying the Emperor by Vandire. In the aftermath, the Ecclesiarchy was reformed, and the Brides of the Emperor were reformed into the Adeptus Sororitas, the Sisters of Battle, the armed forces of the Ecclesiarchy and the Chamber Militant of the Inquisition's Ordo Hereticus.

The Black Crusades (M31 - M41)
A Black Crusade is a term used to describe a number of mass incursions by Chaos Space Marines and the other forces of Chaos into Imperial space from the Eye of Terror. The most prominent of these are crusades led by the Black Legion's Warmaster Abaddon the Despoiler.

The Gothic War (12th Black Crusade)
The Gothic War is the common name for the wider conflict stimulated by Warmaster Abaddon's twelfth Black Crusade (Chambers 1999), which spanned the dates 139-160.M41. The conflict was fought almost entirely around the Gothic sector of Imperial space. The 21-year war resulted in millions of casualties, at least one Imperial world completey obliterated, many ships destroyed and many important personalities killed or incapacitated. Most significantly, the events of the Gothic War revealed the true nature and purpose of the ancient spaceborne alien artefacts known to the Imperium as the Blackstone Fortresses.

Early Raids
The action begins as described in the Battlefleet Gothic book with (presumably Abaddon's) forces raiding a monitoring station on the isolated world of Arx. The protagonists in the book however do not appreciate the significance of this event until further attacks on outposts and shipping throughout Segmentum Obscurus reveal a pattern; mutilation of victims, in some cases the presence of unusual and severe fungal infestations, and not a single attacker - or corpse thereof - recoverable or even evident. It is suggested in the account in the book that the rumours among Naval crew of the reappearance of the Chaos warship Plagueclaw were both true and connected to at least some of the attacks. This is proved obvious when Chaos Space Marines of the Death Guard legion are held responsible for attacking the Morganghast hive world.

Typical to many of Games Workshop's portrayals of emerging galactic conflicts, the account then speaks of warp storms increasing in activity around the Gothic sector and a corresponding increase in unrest of Imperial citizens. This kind of activity in the setting is almost always used to set the scene for a war with Chaos forces and, true to form, the next few paragraphs detail a mounting sequence of strategic attacks by Warmaster Abaddon's forces against targets known - to both he and various protagonists on the Imperial side - through myths and ancient, vague records.

Abaddon's forces sieze two artefacts amid brutal attacks on the planets of Purgatory and Ornsworld, the Chaos Space Marines characteristically obliterating everything in their path and making off with their prizes. The Hand of Darkness and the Eye of Night as the book calls them are later implicated in Abaddon's latest megalomaniac scheme, though they are themselves never described and their exact natures are uncertain - it is however said that the Eldar "spoke of the Hand of Darkness with horror and revulsion". In this setting it is obvious to knowledgeable readers the implications of this; Eldar are frequently implicated as bearers of detailed knowledge on any topics considered 'bad news'.

War Begins
Abaddon's forces and their allies then make a dramatic entrance; warping into locations in the Gothic sector en masse and causing a massive psychic shockwave to sweep through space, which disturbs the Immaterium so greatly that travel into or out of the sector is rendered impossible. They quickly launch large scale fleet attacks on Imperial bases and shipping, crippling many of Battlefleet Gothic's capital ships while still in dock, and destroying numerous orbital stations. This spells very bad news for the Imperial Navy, already stretched thin policing shipping lanes and suppressing local pirate activity.

Events take a further turn for the worse for the Imperium when a fleet commanded by Abaddon himself strikes the naval facility orbiting the planet Rebo V - which is founded around the ancient space fortress known as Blackstone IV. The fortresses, of which six existed in the Gothic Sector and were soon converted into naval facilities, were known to be extraordinarily ancient and lay largely inactive despite the best efforts of the Adeptus Mechanicus to discover their workings. Some functionality was available though, and the Imperial Navy had fitted the stations with as much of their own technology as could be powered, turning them into formidable defensive hardpoints. The Navy was confident of the Blackstones' ability to defend themselves against any fleet attack.

However, as the fleet struck, the Blackstone's systems shut down and the battle station was rendered totally inert. The Imperial fleet defending it was routed by Abaddon's weight of numbers and Blackstone IV was captured.

The 13th Black Crusade
The 13th Black Crusade is the most recent of the incursions against the Imperium by Abbadon the Despoiler, and served as the basis of Games Workshop's 2003 summer campaign. Every race playable in the game fought in this Black Crusade including the Tau, who used the re-deployment of Imperial forces to initiate the Third Sphere Expansion of their empire. The war had massive casualties amongst the Imperium and the Xenos forces with Eldrad Ulthran dying in an attempt to recover a Blackstone Fortress which had been used to devastating effect in space. In the end the forces of Chaos were forced into a stalemate as Battlefleets Obscuras, Solar, Gothic and Pacificus retook control of the Cadian Gate.

Emergence of the Tau Empire (M37-M41)
In the late 37th Millenium the humanoid Tau race was united under the ideology of 'The Greater Good' and underwent rapid technological advances and a large expansion outwards into space where they established a new interstellar empire and settled many worlds in the Milky Way Galaxy. The Imperium of Man only came into contact with the Tau Empire in the 41st Millenium and thus the number of conflicts they have been involved in is minimal compared to the other more numerous and widespread interstellar alien species like the Orks and the Eldar. The expansion of the Tau Empire also caused several other intelligent alien species to be incorporated into its ranks, such as the Kroot and the Vespid. In games of Warhammer 40,000 these races are usuable as Tau allies.

The Necron Resurgence
In the late 41st Millenium the dormant Necrons have awoken to harvest the sentient races of the galaxy for their masters, the C'tan. The cause of the Necrons awakening from their long sleep is debatable, with several theories among Adeptus Mechanicus Magi, including that the Tyranid Hive Mind's shadow in the Warp or an Adeptus Mechanicus Explorator fleet disturbed them. Regardless of their reason for awakening, the Necrons will reap havoc amongst all the peoples of the galaxy

The Tyrannic Wars (745.M41 - Present)
cross-posted from Tyranids

The Tyrannic Wars are the collective conflicts ignited by the Tyranid race's sudden incursion into the Milky Way Galaxy, beginning in 745.M41 by the Imperial Dating System.

Hive Fleet Behemoth
The first recorded encounter with the Tyranids occurred in the Eastern Fringe of the Galaxy and was documented in reports from the planet Tyran. An Adeptus Mechanicus Explorator station at Tyran identified a collection of worlds in the area that had been stripped bare of their biomass and atmosphere. The station was subsequently attacked and consumed. A year later, an Imperial Inquisitor named Kryptman, who received information regarding the attack, arrived on Tyran to investigate. After searching the planet he chanced upon a data codex hidden deep within Tyran's crust, which contained information about the invaders

The information collected by the Explorators on Tyran allowed Kryptman to identify the pattern of attacks and predict the course of the hive fleet. However, these predictions came too late: several more civilisations were wiped out, largely because astropaths could not send psychic requests for help because of a phenomenon known as the "Shadow of the Warp"- somehow, the presence of a hive fleet near a planet stops psychic communication, which is the primary method of interstellar communication used by the Imperium.

The Tyranid force, dubbed "Hive Fleet Behemoth", cut a swathe into the Ultramar sector, the realm of the Ultramarines Chapter of the Adeptus Astartes. Undeterred by the Marines' strike fighters, the fleet reduced Prandium, the garden world once known as the "Jewel of Ultramar," to bare rock.

Eventually, Chapter Master Marneus Calgar mustered his entire force for a last-ditch defense of the Ultramarines' homeworld of Macragge. Here, during the Battle of Macragge, the hive fleet was completely destroyed. However, the Ultramarines suffered heavy losses, losing their entire First Company in a last stand at the northern polar fortress.

Hive Fleet Kraken
The second wave of Tyranids to fight against the Imperium was known as "Hive Fleet Kraken". Instead of throwing one mass of troops against the human armies, this swarm split into countless smaller fleets, each one enveloping whole systems before reinforcements could arrive. Kraken was finally brought to battle on a grand scale at Ichar IV, a Hive World, in 993.M41 (Chambers, 2001). The brunt of this attack was borne by the Scythes of the Emperor and Lamenters chapters of the Space Marines and the Eldar Craftworld Iyanden, all of whom suffered very heavy losses. According to Lieutenant Kage of the Last Chancers penal regiment, the Imperial Guard "Lost over a million men at Ichar IV", though this may serve simply to illustrate in a very broad sense the scale of the battle, as numerically speaking a million soldiers is not a great burden for a Hive World. Kraken was not fully destroyed though, and split into several splinter fleets. There was little respite for the Imperium after Kraken's near destruction as a new hive fleet emerged soon after.

Hive Fleet Leviathan
The third wave of Tyranid attacks, "Hive Fleet Leviathan", appeared from below the galaxy and attacked from two points, cutting off large portions of the galaxy from reinforcements. In order to buy some time, the Imperium, under the command of Inquisitor Kryptman, attempted to redirect the attacks of this fleet towards the Ork-held worlds of the Octavius System. While the plan was a success, the Tyranids have since been steadily working their way through Ork space, suffering massive losses, assimilating everything that stands before them. The Imperium has bought itself a century at least to prepare for the next attack, but there is no telling how the Tyranids may evolve thanks to the newly-harvested Orkoid DNA.

Hive Fleet Leviathan also attacked around the same time as Hive Fleet Kraken, making both fleets difficult to deal with as one or the other would provoke some sort of uprising or invasion. To date, Behemoth is the only Tyranid Hive Fleet that did not utilize the "tendril" tactic, suffering the consequences.