Ragnarok

Overview
October 30th, 2345, known as Ragnarok to humans, was the day of the Exohuman attack on Earth, and is responsible for the start of the Human-Exohuman War that followed. Ragnarok was a massive surprise attack, and is considered the most devastating military defeat in all recorded human history due to the massive casualties taken over the course of the day. Ragnarok also allowed the Exohuman forces to set up permanent facilities on Earth to further extend their reach and support their war effort, even using captured civilians and soldiers as labor workers for many years after.

Prelude
A month before Ragnarok struck, the UNMC Sol System Fleet had made first contact with the enemies they would call "Exohumans" in the short but costly First Contact Battle. As a result of the battle and the realization that the Exohumans were a huge threat to the UNC, all UNMC lines were bolstered throughout the Sol System, especially Earth which received an increased fleet of 300 ships along with 50,000 more UNAC and UN Army infantry forces giving Earth over 3 million active ground forces. The UNC thought this to be more than enough military might to face off with their newfound enemies, as the UNMC had enjoyed a constant military superiority for more than half a century. However, they would soon discover that even this would not be enough to hold back the full might of the Exohuman Advance Fleet.

The Battle
On the morning of October 30th, Exohuman warships were picked up on UNMC radar appearing all across the system, which prompted UN forces to investigate while also drawing several battlegroups away from Earth. After several minutes of jumps all over Sol, Exohuman ships began to close in on Earth's perimeter, at first registering dozens of ships. UN forces consolidated around Earth's orbit to intercept the enemy ships, but many were still on their way when the Exohuman forces revealed their true strength. Hundreds of ships transitioned out of I.T. Just a few dozen kilometers from the UNMC fleet's lines, numbering well over 400 to face the UNNF's 200 vessels in space. The UNMC immediately split their forces in an attempt to draw the hostiles away to allow time to evacuate the UNC Council who were currently aboard Rashiba Station, but many Exohuman ships completely ignored the UN and rushed to the surface to deploy ground forces and commence with bombardment. Now scattered and confused, the UNNF fleet tried everything to hold off the invaders. Launching WMDs at Exohuman lines, managing to destroy dozens of Exohuman ships, however they had already taken so many casualties that the battle simply became a numbers fight, and within minutes the entire orbital fleet line was broken into peices by the Exohumans. At this point, the Sol System fleet had already been reduced to barely over 100 ships, while the Exohuman fleet still numbered over 300. Earth commanders ordered all remaining ships to cease orbital operations and retreat planetside to defend the cities and deploy troops in a desperate attempt to save any land they could. Exohuman forces gathered mostly over Earth's eastern hemisphere to target the vast amount of land and UNMC installations and proceeded to completely destroy anything they could reach. After only an hour of occupation, 70% of the UNMC forces in the east had been killed or lost contact with, billions were already dead or beyond saving, and most of the major cities in the eastern hemisphere had been blasted apart by the Exohuman fleet, which then started to advance on the western hemisphere with hordes of ground and air forces. However, the reluctant sacrifice of the east by the UNMC allowed them to prepare and build up a sizable defensive in the west, especially focused around Europe (which was home to Paris, the UNC capital). UNMC lines were also held in North America and South America, with air and seafaring naval forces using Africa as a distraction to draw away Exohuman air from Europe and the Americas. When Exohuman forces did finally reach the west, they were met with heavy resistance from the remainder of the Sol System Fleet, with about 60 of the ships belonging to the UNAC commanded by General Christian Green, and about 30 under the command of the UNNF's Arch Admiral Mikihal Selfridge, with ship commanders burning with revenge for their lost naval forces. Under the expert tactical planning between these two men, the SSF was able to hold off a large number of Exohuman vessels from decimating the important military centers placed throughout Canada and the U.S. although they were visibly suffering from the loss of advanced communication centers and suppliers in Asia and Australia. UNMC ground troops put up a fierce defense using whole battalions of tanks, artillery, and vehicles available to them to inflict heavy losses on Exohuman infantry. But just like the orbital battle, the ground fight started to be overwhelmed due to the massive amount of Exohuman forces. After hours of fighting, the UNMC had to face the fact that they simply could not hold off the Exohumans all day long, and began to pull back forces to defend only key points in the west. This retreat allowed Exohumans to gain a foothold on the eastern seaboard of the U.S. as well as half of Canada and almost 2/3 of South America. They continued inflicting hits to the UNMC's morale by unleashing Megaton Bombs on core cities of the American National Alliance which ultimately resulted in large portions of Canada being annihilated completely.

UNMC defeat
The fight continued on with the UNMC taking more and more losses and the Exohumans gaining more land as the day drew on, and by the end of the day the Earth forces were nearly to the point of collapse, and waiting desperately for reinforcements from Valde Suggero, the closest UNC colony to Earth. By the end of the day, the remaining 200 Exohuman ships split their force in half, keeping one half on Earth to hunt down the 60 or so remaining UNNF/UNAC ships. The other half were unleashed into the Sol System to find and destroy any UNMC colonies, space stations and installations they could find, with their inhabitants now trapped helplessly with no ships. Exohuman ships hunted and destroyed most of the remaining UNC colonies and space installations in the system, killing an additional estimated 75,000 people.

Help arrives
By the early morning of the next day, UNMC reinforcements had arrived in Sol, giving much needed relief. Exohuman ships not at Earth were targeted and destroyed by elements of the UNNF 1st Fleet and UNAC 68th Fleet, while the entirety of the UNAC's 5th and 41st fleets assisted the forces on Earth. By the end of October 31st, the casualty report was staggering, a projected total of 4.3 billion civilians and military personnel of Earth's 12 billion killed, with a large amount of the rest predicted to be trapped, hiding or captured. Military casualties rose above 70% for ground forces, and above 80% for the Sol System Fleet. The UNMC was now fully dedicated to the war, pledging to drive the Exohumans from Earth and defeat them on Mars whatever the cost.

Aftermath
In the following weeks, recruitment for all UNMC branches skyrocketed, supplemented by a massvie influx of civilian personnel wishing to take jobs in the military as well. People from all over UNC space rushed to Earth's defense, with many of them relocating to closer planets, while many more also chose to flee any colonies considerably close to Earth, causing flucuations in many colony populations for years after. The UNMC would continue to evacuate any civilians that were left on the planet for years after Ragnarok, calling in most of the fleet's carriers to transport them away to other colonies, the Navy even began to use Colonization ships to help with evacuation. Thousands of refugees were transported everyday out of the zones the UNMC could save, which for the first couple years was a good percentage of the planet. The UNC estimated that 75 percent of the original remaining residents of Earth were evacuated between 2345 and 2353. Even after this estimate, the UN would continue to search for any remaining civilians anywhere they could, and were successful in finding pockets of human survivors sporadically over the following years.