This is my take on what happened after Half-Life 2: Episode 3, or at least Marc Laidlaw's version of it. This was done with the help of Municipal Engines and, both of whom were a great help to this project.

The Resonance Cascade of 2003 was an event of unparalleled significance for humanity and Earth. It brought about portal storms and the resulting incursions, the first wave of which included Xen infestations, Race X missions to establish footholds, Strogg raids, and, of course, the Seven Hour War and the Combine occupation of Earth. All of these had catastrophic impacts on baseline human population, reducing it by 90%, further exacerbated by the Combine's Suppression Field that prevented human reproduction through the disabling of certain protein chains important to the process of embryonic development.

The Xen lifeforms, many of which originated from worlds further afield, thrived in the warmest, wettest parts of Earth. The introduction of multiple invasive species caused a collapse of many local biospheres, leading to widespread extinctions and associated famines. Economies collapsed, wars started, countrysides were evacuated. Much of what was left of the human population was moved to the cities, defended by what remained of Earth’s military forces. There, they were targets for the forces of the Universal Union, or as they would later be called, the Combine.

The Seven Hour War was a wholesale destruction of humanity. Even after Breen negotiated humanity's surrender in a burning New York, the Combine systematically obliterated hundreds more cities that they missed. They preferred to use the middling towns and small cities of Earth for their new collaborationist human reservations, and it was far too much effort to try and micromanage cities like New York, London or Beijing. So they had to be finished off, regardless of whether the human survivors had finished evacuating or not.

During the Combine occupation, most of humanity's surviving former military was re-purposed into the Overwatch and Civil Protection. These forces were either sent to the frontlines of Earth to secure important resources and maintain civil unity, or to off-world garrisons and conflicts. Surprisingly little remained in the occupied urban centers and their corresponding regions to watch over the subjugated citizens. This was in part why the Lambda Revolution saw so much success.

The Lambda Revolution was instigated in Zone 17, the Combine designation for the Balkans and Western Black Sea. The Lambda Resistance (known by its members as just the Resistance) was led by former Black Mesa personnel and was the chief anti-Combine operator in Zone 17. Though small and ill-equipped, the Resistance had advantages in the form of dedicated, skilled soldiers and scientists, the majority of the free Vortigaunts on Earth, and the man known as Gordon Freeman. This individual would become a hero in the eyes of the world for his numerous acts of sabotage and rebellion against the Combine during their occupation, culminating in the destruction of Citadel 17, the chief and largest Combine command installation on Earth. Its destruction resulted in the death of the centralized collaborationist regime and the elimination of the bulk of the Combine communications and military-industrial complex. With the head lopped off of the snake, the alien occupiers' fortunes began to unravel.

Earth, at least this particular incarnation of the planet, was always a backwater. The breadth of the Universal Union meant that it was just one occupied planet out of quintillions, possibly septillions; the Auditors of the Union could not keep track of the exact number. Local Advisors could never count on the Overworld to discover that Earth had fallen, and it was Combine protocol that local Combine forces have a responsibility to inform the Overworld of any unrest that they themselves could not handle.

Even contact is no guarantee of aid. Although it would take but a mere fraction of a sliver of the Combine's forces to reconquer Earth a thousand times over, the Universal Union had other, more pressing wars to fight. The Overworld could reassign one of the Combine's great orbital fleets to subdue Earth, but it had galactic empires with actual spacefaring forces to fight; such was the weakness of Earth that the Overworld deigned it an inappropriate use of void-based forces during the Seven Hour War. Even planetary forces were inappropriate: the Universal Union had countless enemies, which required particular attention to fight. The corrupting Malignant Exogens, the ravenous Biotic Consumers, the sociopathic Kwamunidalak, the madness-inducing Anomalous Parasites, the horrendous creatures of the Todash spaces; there was a reason that the Universal Union practiced mass conscription of its subject species and sent them off for "permanent offworld reassignment." No help was arriving.

Collaborators across the globe turned inward, each zone effectively becoming independent. Administrator Breen's subordinate officials, the Moderators, wrestled and struggled for control over the Combine state apparatus. Many succeeded in retaining their power and new-found independence, others fell to rebels, remnant human hermit-enclaves emerging from their hidey-holes, alien forces, and the vestiges of the Combine proper led by Shu'ulathoi, what humans designated as "Advisors." The destruction of City 17, the failure of Breen’s attempt to contact the Overworld, and the failure to secure the Borealis, shattered any sense of Combine unity.

Some Advisors remained loyal to the Overworld. They understood the implications of human teleportation technology, and knew that if this technology were disseminated to the rest of the Universal Union, they could start making real gains in their countless wars. However, with many Combine remnants pursuing their own agendas, and the Loyalists themselves disagreeing with the future of Earth, they have not achieved the success they might have. Many Loyalists still attempt to contact the Overworld, although others realize the futility of this cause as there is no dark energy reactor on Earth powerful enough to fire the signal to the Overworld, especially past human jamming and renewed portal storms. The human-built “Bootstrap Device,” found on the Borealis, would have been powerful enough to get a signal to the Overworld, but Combine forces were unable to secure the device before the One Free Man stole it and used it as a crude – and completely ineffective – battering ram against a Combine military installation. Still, efforts continue to both contact the Overworld and find whatever remnants of human technology they can find. The Advisors hope that they will be richly rewarded by the Combine leadership for delivering this wonderful prize to them.

Other Advisors have deemed contacting the Overworld a lost cause, or for their own reasons have decide that contacting the Overworld is a bad idea. Earth, being a backwater, was attractive to lower-end Advisors, and knowledge of human teleportation technology gave some of the most ambitious Advisors inklings of glory. When contact with the Overworld collapsed, these more ambitious Advisors sought to forge their own local empires. Calling themselves the “True Combine,” they want to create, at the very least, a planetary empire away from the Overworld’s meddling. Attitudes on mankind vary among the True Combine: some are content to have them as slaves that retain their free will, others wish to convert them to Stalkers, others still want them exterminated and replaced with more reliable synth forms. Whatever their attitude, they are universally opposed to both Loyalists and the human states, and also to one another.

One particularly successful group of Advisors believed they can do better than the old Universal Union. Calling themselves the Transuniversal Coalition, they sought to create a multi-species empire that allowed each species to play a role, in exchange for guaranteed rights. Humans and Vortigaunts will continue to serve, but they will do so voluntarily. Gone is the Suppression Field and the forced transhumanism, each species will serve freely. While the Advisors have a primary role in government, human and Vortigaunt moderators are not complete puppets, but instead are chosen by their communities to voice their opinions. The synths, of course, were never liberated, as they are physically incapable of conscious thought. The Transuniversal Coalition hopes to secure Earth, establishing its new, more just order, and from there move on to the rest of the universe. They already have some contacts in Xen, and the remnants of the Nihilanth’s armies are interested in an alliance. Already, alien grunts and alien controllers have been seen on Earth, fighting in the Coalition’s ranks.

But the Combine did not rely on Advisors alone. Doctor Breen was allowed to appoint "Moderators," other human collaborators. Most of these were scientific personnel, as Breen favored fellow scientists, who believed in the vision of a better humanity through working with an obviously more advanced alien species. After the fall of City 17, some have gone rogue and set themselves up as petty tyrants, using transhuman forces to kill the local Advisors. Some have since tried to ingratiate themselves with a newly freed humanity, presenting themselves as liberators, or even aligning themselves with the Lambda Republic. Others, such as the collaborators in Section 28, still claim to be part of the Universal Union for propaganda reasons or for fear of the Overworld’s return return, and because the stranded Advisors have taken more effective control of the regions. It is common, however, for Moderator-led states to adopt transhumanism, and to rely on Overwatch forces more than other post-Combine assets. Having some knowledge of the Combine’s abilities and what the rest of the multiverse is like, they believe that humanity could only be saved by adopting Combine technology, or otherwise modifying themselves.

Some believed in the Combine’s message of salvation through technology. Foremost among them was Doctor Wallace Breen, former administrator of Earth on behalf of the Universal Union. Former in more ways than one: this new Wallace Breen was merely an old copy of his mind, transferred to an Advisor’s body. The original had long since perished, but this new Breen was well aware of what had happened to his original self. After a chance meeting with Gordon Freeman, his original’s assassin, he was spared by the would-be savior of mankind, and Breen decided to make a positive change for humanity. Realizing that he had betrayed all he stood for by serving the Combine willingly, he sought to genuinely improve humanity, with himself at the helm. Dubbing himself the True Benefactor, he seized control of remaining Combine forces in the Arctic, and attempted to seize total control before other Combine factions revoked his security clearances. From his base in Trondheim, the True Benefactor reprogrammed his transhuman forces – both legacy Combine units and those he would create himself – into believing that they were always serving humanity first. This allowed the True Benefactor’s forces to be extremely effective, even against larger armies. Collaborating with their idealistic Moderators, and even Vortigaunts, the True Benefactor formed his new Combine, a “post-species” political entity bent on giving all sapients improvement through technology. Here, citizens are uploading themselves into new bodies on a larger scale than elsewhere in the world, discarding boundaries between man, alien and machine. Transhuman-made synths and human mind-uploads abound, and citizenship is extended to all species, especially any new form of human that arises. Of course, the True Benefactor retains his position as supreme leader.

By far the most common regime post-City 17 are those forged by Civil Protection units. With many Overwatch and synth units destroyed in wars between the Advisors and the Moderators, Civil Protection units were left as the most heavily armed, regular humans on most of the Earth’s surface. These Civil Protection units most often established themselves as warlord states or military dictatorships, while some became roving bands that terrorized small communities. While urban Civil Protection units were often composed of a multitude of ethnicities, as the Combine moved them to the major Cities, most Civil Protection units were composed of police and military forces from before the Seven Hour War, and later local recruits. As a result, there is a tendency for Civil Protection dictatorships to take on the symbols and culture of the old countries, if in a warped, somewhat-misremembered way.

The remnants of the Lambda Resistance formed a multi-species state from the ruins of the Balkans. Calling itself the Lambda Republic, it is one of the few states that guarantees rights to all humans and Vortigaunts, the latter still despised and distrusted by most of humanity thanks to lingering memories of the Resonance Cascade. The Republic was founded on the principle of survival, and beyond that, freedom and equality. Many people of the Lambda Republic were Americans, those living around the Resonance Cascade zone, moved to the Balkans by the Combine so they can keep an eye on former Black Mesa staff. This American population remains somewhat separated from the local Balkan population, to say nothing of the Vortigaunts, who often live in caves or villages of their own construction, totally separate from human communities.

The Republic is governed by a single Senate, which is composed of both elected community leaders and the old Black Mesa staff, who formed a de facto aristocracy. As the years ground on, the Black Mesa staff’s descendants did become an aristocracy, deeming themselves to be more intelligent than the elected members, some of whom could not even read due to the dearth of formal education among the Lambda Republic’s territories. The Black Mesa elite thus retain a superior status, although other members of the Senate and the citizens of the Lambda Republic as a whole accept this order, as they do prove to be rather intelligent. It is the practice preventing intermarriage between Black Mesa families and other, regular humans that is starting to raise eyebrows.

The glue that is increasingly responsible for holding together the Lambda Republic is the “church” of the One Free Man. After Gordon Freeman’s disappearance, tales of his apotheosis spread, particularly as the more spiritual Vortigaunts continued to laud the man’s actions. Combined with his truly amazing feats, and children growing up hearing about this mythological Free Man’s accomplishments, and it is no wonder that a church has arisen around the figure. The One Free Man is believed to have become a god, wiser and stronger than any man, and that he will return on the fabled “third day.” Many acolytes wait patiently for his return, looking for portents in the stars, in the clouds, in their soup, for a sign that Freeman is returning. The leadership of the Lambda Republic have taken advantage of this devotion, claiming through their research to be working on finding Freeman so that he may repair mankind and drive the Combine off Earth once and for all. Others are more skeptical, believing that the Lambda Republic’s leadership are simply using Freeman’s legacy to advance their own wealth and power, and that even though they may wish for Freeman to come back, that it will never happen. Others still claim that the leadership have found Freeman, and have stored him in stasis until the time is right to release him to the world.

Other countries are what are termed “paleonationalists.” Rather than follow the Lambda Republic’s message, they are distinct remnants of old Earth governments. The most powerful example is the United States of America, which has returned from its exile in Xen. Ever since the Montauk Project, the highest echelons of the American government have been aware of other universes, and the threats that may arise from there. It was during this time that the enigmatic figure known as the “Gman” made itself known to the American government, giving dire portents of doom, and recommended using Xen as a refuge. Thus, the Nixon administration ordered the creation of the Black Mesa Research Facility, to study these phenomena in greater detail, and eventually create a continuity of government option safe from both potential alien invasion and Soviet attack. By the late 1980s, the first incursions into the border world of Xen were made, and secret facilities were constructed there. These facilities were not unlike Black Mesa on Earth.

When the Resonance Cascade happened, there was already a small population of scientists living on a semi-permanent basis in the border world, and the Cascade was a signal that the United States government had to evacuate. The Gman informed the Presidency just moments before the Resonance Cascade what was about to happen, and that whatever Black Mesa staff which weren’t going to be evacuated should be eliminated, lest they fall into the hands of a greater enemy. The HECU succeeded in their mission, and even launched a counter-invasion into Xen to pave the way for the evacuation effort. The President, Vice President, the Cabinet, the Joint Chiefs of Staff, most of Congress, and even half of the Supreme Court and their families were successfully evacuated, including America’s top military brass, intelligence agents, select science staff, units of the HECU, and even civilian government workers selected for their genetic viability.

The United States government persisted in exile, studying Xen life and continuing the research conducted in Black Mesa, albeit with a focus on weapons. New war machines were constructed, to supplement those that had been stored away over the decades and those that made their way to Xen during and after the Resonance Cascade. The Americans kept somewhat abreast of events on Earth, although much of the information they had was provided by the Gman. Suddenly, the Gman informed them that the Combine had been cut off from Earth, and now was the perfect time to attack. American forces made their way back to North America, cutting through disorganized Combine forces and recruiting many American Civil Protection units to their cause. The Americans were hailed as liberators, and they soon fought and defeated Loyalist Combine forces and driving them north and east. The United States, at least in part, was reformed.

Relations with the Lambda Republic were initially friendly, but chilly. The Black Mesa staff that made up the Lambda Republic’s leadership still remember their coworkers being slaughtered by the HECU, while the Americans are wary of the Lambda Republic’s cushy relation with one of their old enemies, the Vortigaunts. This animosity has cooled down since the old generations have passed on, but there remain core disagreements over the use of technology. The Americans are rather more cavalier about portal technology than their Lambda counterparts, who urge caution when playing with the forces which caused the Resonance Cascade to begin with.

The Americans were not the only nation to have an interdimensional research program. The European Community had one of their own, under the guise of the European Organization for Nuclear Research, or CERN. Although some had suspected that CERN was up to something beyond smashing subatomic particles together, nobody believed them until the Resonance Cascade. The Europeans had actually succeeded in discovering Xen for themselves, and also had contacts with the Gman. A refuge, smaller than the American counterpart, was built in Xen, along with a series of Alpine shelters. After the Combine retreat, the Europeans have expanded through Central Europe, which were devastated in inter-Combine wars. Outwardly, the European Emergency Council has the revanchist goal of liberating all of Europe and restoring the old nations, reasserting European culture and values where they have been destroyed.

Although the Europeans are outwardly friendly with the Lambda Republic, their leadership has ulterior motives for this alliance. The Lambda Republic has control of the ruins of City 17, and with it, the destroyed Citadel. Even prior to their exile, the leaders of CERN had more esoteric goals in mind. Calling themselves the Disciples of New Babel, the CERN leadership hoped to unite humanity under one common system, ascend through the use of technology, and commune with the “gods” as equals. During their long exile, this religion became mainstream among the Europeans, and they took this with them back to Earth. The Europeans do openly conduct exploration into Xen, which the Lambda Republic frowns upon, and more concerning to the Lambda, they allow some ostensibly-Abrahamic faithful to use these expeditions to find “Heaven.” Although most of the faithful openly advocate for safe and regulated interdimensional travel, there are radicals in the leadership, who wish to advance humanity and find the gods by any means necessary. These radicals plan on rebuilding the Citadel, and using it as a new Tower of Babel to commune with the gods.

Other remnants are out there that have loosely aligned with the Lambda Republic. The Japanese government, which hid in undersea bases around Hokkaido, has retaken that island and Sakhalin. They are busy fighting the artificial intelligence which has taken control of the Home Islands, but it may be a futile fight, as the Japanese home islands were scoured of life during the Seven Hour War and the subsequent collapse of Combine order. In the outback, remnants of the Canadian, Australian, New Zealander, and British governments were working on their own, Commonwealth version of Black Mesa, but only succeeded in creating a national refuge for the monarchy thanks to constant budget cuts. The royals never made it to Australia, which has made the project a rather moot thing. Although most of the Australian continent is under Loyalist control, the CANZUK have adapted, raiding the Combine for resources.

The Russian remnant sought to take as much Combine technology as possible and repurpose it for their own ends. Made up of the nation’s top scientists and military leaders, who had hidden away in Cold War bases deep in the Urals, the remnants of the Russian Federation saw the Combine’s way as the way forward, although with humanity at the top. This new Posthuman Union is not unlike the Combine they replaced, maintaining Civil Protection units (down to the name), and creating their own Overwatch using repurposed Combine laboratories and factories. They are led by a cadre of posthumans, who modified themselves using captured Combine technology and have rendered themselves all but immortal. Rather than weakening their physical forms, like the Advisors did, they used genetic engineering and cybernetics to create better bodies for themselves. The Posthumans have established a class system, where the unaugmented and unenhanced are at the bottom of the social pyramid, to toil away for those above them. Those who have some cybernetic augmentations or bio-engineered hybrid organs are in the middle class. Those who have fully embraced posthumanity and have placed their minds into machine forms, or have become indistinguishable from synth, make up the upper classes. This system is justified by the Posthumans to reward those who are the most willing to embrace the new future of humanity. In the near future, the decision will no longer be voluntary.

The Resonance Cascade's effects were not felt at all in Afghanistan. The war-torn country was already deeply impoverished and cut off from global trade, so the economic crises and the collapse of global trade that came with the death throes of American military and economic hegemony had little effect on the landlocked country. While the creatures from the Border World devastated ecologies worldwide, they had little purchase in the arid, mountainous climate of Afghanistan, their home dimensions being rather more humid. At any rate, they had few fauna to feed on, and the battle-hardened Afghans quickly proved themselves more than capable of dispatching dangerous creatures such as headcrabs. The concern of the average Afghan was the same - surviving the day to day. Perhaps unsurprisingly, the concern of the various mujahideen groups remained that of political dominance over the country, and not the world that slowly crumbled around them.

The Combine invasion changed nothing. The mountainous country, deemed an absolute non-threat by Combine strategic analysts, was completely ignored as during the Seven Hour War. Although the Afghan representatives with the United Nations accepted Wallace Breen's surrender on behalf of the entire species, the Afghan leaders on the ground paid them no heed. They never listened before, why should they start now? During the occupation, the Combine paid little attention to Afghanistan. There were no important resources there, so apart from razing Kabul and establishing a small garrison, the Combine did little. The Afghan factions did take the Combine invasion to mean a renewed jihad, against an alien enemy that does not know the light of God and is likely serving under Satan himself. This stopped the large-scale infighting, and the Afghans did what they have always done whenever an invader moves through their lands: retreat to the mountains.

From there, the Afghans launched intermittent attacks on the Combine; a particularly daring raid, led by the Saudi fanatic Osama bin Laden, succeeded in ending the Combine's attempts to repair what few rail lines ran through the country. The Afghans raided Combine weapons depots, taking their advanced weaponry for themselves; one would be amazed to see the incongruous sight of Afghan warriors on horseback, wielding rifles which used dark energy as ammunition. Combine attempts to crush these anticitizens failed. Headcrab shells may destroy one settlement, but headcrabs seldom lived long enough to infect other areas. Helicopters proved useless, as like the Soviets before them, the Combine learned that the Afghans were adept at destroying gunships. The synths brought to pacify Earth did not fight well in the mountains, with specialized mountain units being utilized in more important offworld operations. Of course, the Combine did not direct much of their efforts against the Afghans; a backwater region on a backwater planet deserved no attention from the Overworld. At any rate, local Advisers determined that the Suppression Field would soon reduce the entire Afghan population to feeble old men and women, which could be easily dispatched. On top of that, the planet would be uninhabitable to all native lifeforms in the course of a few centuries. Expending the military resources necessary to fight against mountain rebels is a total waste.

After the fall of City 17, local Combine force found themselves leaderless and without reinforcements. The Combine garrison was weakened by infighting between metrocop and transhuman and synth forces, a weakness the Afghans exploited. Surrounding the ruins of Kabul, the mujahideen successfully destroyed the last remnants of Combine rule in the region, establishing the Islamic Republic of Afghanistan. In the wake of the Combine invasion, other Islamic communities have turned to apocalyptic death occultism, which fed into the new mujihadeen. Many apostates, who abandoned Islam on the orders of the Combine, were put to the sword. Today, the Afghans want nothing more than eternal jihad, to punish every infidel, and hopefully in this way the Ummah can regain favor with God for abandoning him in the face of his ultimate test. Their coreligionists have spread their word of holy war throughout the Middle East, forming terror cells at war with the Combine occupiers responsible for desecrating the holy sites of Mecca, Medina and Jerusalem. Being able to offer food, gasoline, and ammunition, these cells have little difficulty finding new recruits.

From deep in the mountains of the Korean Peninsula, the Purest Race emerged, scathed but triumphant. The Dear Leader Kim Il-sung was wise to build the National Redoubt during the height of tensions with the Imperialists and Revisionists. Running across the entire length of the Korean Peninsula, powered by nuclear power plants the greedy West unjustly kept from them, almost half of the entire population of the Democratic People’s Republic of Korea could survive in these former coal mines indefinitely. Food would be provided by mushrooms and rations to last for decades, air by a series of ventilation shafts hidden across the countryside, defense by mines, trap doors, false paths, and the will of the Korean people. As their southern brethren were overrun by terrible monsters brought to the shores of Choson by their cosmopolitanism, the Great Leader Kim Jong-il ordered his people to take refuge in the National Redoubt. It was no retreat, but a tactical withdrawal. Retreats are made in cowardice, while withdrawals are sure to pay off with final victory.

The alien invaders that followed never dared to attack the Korean people, such was their fear that they never even dared to look for them. But the Great Leader watched what was happening in the land above, weeping as he saw his great land defiled by the alien. He instructed the Korean people to make every sacrifice necessary to survive, even if that meant consuming their own dead, but this Second Arduous Struggle was not enough to break the Korean people. The Great Generalissimo passed on to be reunited with his father, and was succeeded by the next scion of the Mount Paektu bloodline, the Glorious Leader Kim Jong-un. It was Kim Jong-un who promised his people that their days of hiding will end under his reign, and it was so. One day, the Glorious Leader proclaimed that the alien invader was swept to the hell from whence they came, and it was now safe to emerge and rebuild.

And rebuild the Korean people did. The aliens had done little to harm the land of Choson, as it was largely unchanged; perhaps, the Glorious Leader opined, even their foreign minds understood the inherent beauty of Korea. The forces of the Korean People’s Army secured the entire peninsula, fulfilling another promise made by the Mount Paektu bloodline: the reunification of all of Korea’s ancestral lands. A few of their brothers remained living on the surface, telling stories of horror, starvation, deprivation and tyranny. The Glorious Leader promised them that those days were long over. These liberated brethren taught the Koreans how to operate the aliens’ strange technology, which the Glorious Leader directed his people to use. Thus, he laid the foundations for the modern Korean state.

The transplanted peoples in Korea had to go, of course. The land belonged to the Purest Race, so the Glorious Leader triumphantly relocated them to their true homelands. Much of East Asia remained under the control of the alien, and that simply would not do. To this end, the Glorious Leader has prepared for a great war against the warlords and conquerors occupying the lands of Asia, but in his wisdom, understands that now is not the time for such a struggle.

From deep in the bowels of the Aperture Science facility, GLaDOS has expanded her grasp. While she is fundamentally interested in testing portal test chambers, she does realize that other powers want to have portal technology, and her Aperture Science programming simply would not allow competitors to seize intellectual property by force. The Combine already made an attempt, successfully capturing an Aperture Science handheld portal device after the fall of City 17, although their engineers proved incapable of making Aperture Science portal technology work without lunar dust, let alone transforming it into the teleportation technology they desired. Knowing this raid was not going to be the last, GLaDOS made her move, deploying armed war machines to the surface and cleansing it of almost all human and Combine life, unless they made promising test subjects. With nigh-inexhaustible natural resources, GLaDOS overwhelmed even the Combine forces that remained, until she created a buffer zone she was happy with. Now, she can test in relative peace.

The destruction of City 17 created a new dimensional event that, though much smaller in scale than the previous, created enough global resonance to allow for reinvigorated portal storms. These set off Earth's location on the multiversal quantum radar for a great many watchful powers. One by one, new interlopers poked their nose into the devastated world's affairs. Some, recognizing the extent of the damage and seeing direct evidence of the Universal Union’s capabilities, fled and hoped nothing would follow them. Infinity Patrol expunged what they dubbed “Cascade-2” from their records, officially marking it as a puzzle world from which no patrol can return. Only the upper echelons of Infinity Patrol know the truth, as does Centrum command, as part of a clandestine information sharing program on threats to both blocs’ corner of the multiverse. Persephone Aerospace, familiar with the Universal Union’s work, fled the timeline after procuring some Aperture Science robots. The Pact of Silence, true to their name, never spoke of this world.

Others remained, but kept a low profile or failed to establish an effective foothold on Earth. The Directorate of State Security established a listening post in trans-Neptunian space, but otherwise kept their distance. The Strogg continued their raids, but post-Combine resistance eventually rallied and now Strogg raids are a rarity. An attempt by a True Combine faction to harness Argent Energy in lieu of the less efficient dark energy plasma the Combine usually used ended in disaster, but the situation was contained by an invasion of neighboring Combine states.

Race X, which was all but driven off Earth during the Combine invasion, launched a second invasion which saw them taking control of vast swathes of territory. Always militarily inferior to the Universal Union and the other “heavyweights” of the multiverse, the leadership of Race X sought instead to pick at the scraps the large empires would leave behind as the balance of power shifted. The initial invasion during the Resonance Cascade was one of opportunism, hoping to capture Earth without the Combine noticing the events that were unfolding. When Race X detected the preparations for the Seven Hour War, they beat a hasty retreat, momentarily convincing the human defenders that the worst was behind them.

With the Combine gone, Race X moved to take advantage. They poured through the zero point of the Resonance Cascade, knowing that they could move far more troops through that gaping wound in the universe and afford to lose whatever troops are destroyed by the portal storms. They targeted Earth’s jungles and rainforests, knowing such environments would be most familiar to them. Already sparsely populated because of Xen infestation and ignored by the Combine, the Race X forces swept aside whatever remaining Combine resistance was in those regions. From there, they began their xenoforming mission, hoping that the Overworld does not catch wind of their plan.

Not all of the alien controllers joined the Transuniversal Coalition. Others sought a new homeland, one not as hostile as Xen, and found it on Earth. These alien controllers are rather weak compared to their neighbors, all of whom have a reason to despise them, but they have struck a strategic alliance with Race X. The alien controllers can provide technology and troop types that Race X is lacking, and in this way they act as mercenaries for Race X. They have proved rather effective, leading to human and Combine factions to take notice.

The only human force from beyond to establish a permanent base of operations on Earth is the forces from the Third Reich. The Reich was fanatical in its expansion through the multiverse, carrying out Hitler’s final orders. Hitler, knowing of his empire’s fate in other timelines through film reels from these other places, knew of the existence of interdimensional travel and the need for the Reich to propagate itself. Thus, he gave orders to establish outposts wherever possible, even if the danger is great. True to their Fuhrer’s will, the Third Reich has established a base in the Alps, where they have a tense but non-hostile relationship with the Europeans, who were understandably horrified by the arrival of the Nazis but were unwilling as yet to make an enemy of them. The Reich has exhibited a bile fascination with Combine transhumanism, seeking to perhaps integrate it into their ever-advancing technological package.

The entity behind this entire mess, the Gman, is rather pleased. A hired gun, so to speak, he has been in the employ of forces that have the goal of stopping the Combine’s advance through the multiverse. With his efforts, he has succeeded in stopping the Combine from recovering local teleportation technology, and his comrades do the same elsewhere in the multiverse. The Universal Union would have discovered Earth and Black Mesa eventually, so a premature Resonance Cascade, supporting Freeman, and the ensuing chaos…everything went just as planned. Of course, the Vortigaunts have reason to oppose this enigmatic figure: the Gman’s employers are far from pleasant, and some may prefer the Universal Union to their cold grip.