Story
Sixty five million years ago a vast colony ship was sent to the Earth from a distant alien world. As the enormous craft approached the infant planet a massive and violent solar flare caused a navigation systems faliure. Crippled and failing the vast bulk plummeted through the stratosphere to emerge into Cretaceous skies. On the Earth innumerable species of life gazed skywards as their nemesis ploughed into the planet.
A vast cloud of dust clogged the atmosphere and as the land cooled, so the dominant life, the mighty dinosaurs, perished. But the 400 billion tons of T'leth* was not destroyed in the impact, sophisticated super computers initiated a cryogenic sleep cycle for the creatures deep within its holds. As the aeons passed the computers woke parties of aliens to attempt communication with their stellar cousins, all in vain for the core of the alien power slept on.
1999-2002
This is not the place to speak of the First Alien War in detail, but in 1999, Earth engages in a war with unknown aliens. X-Com, short for the Extraterrestrial Combat Unit is set up by the United Nations in order to solve the problem to the alien threat. After many countless battles and loss it appears that Earth is fighting a losing battle. Interrogations made by X-Com personnel and the bizarre alien ‘plasma’ technology as well as new construction and power sources are studied, forming hybrid spacecraft, new formidable weapons and the ability to unlock psychic potential in Humans. The intentions of the aliens are made clear as governments become infiltrated by Alien operatives, secretly allying with the Aliens through the promise of technology, peace and prosperity, pulling out of the X-Com project seeing it as a wasted operation. As the war drags on, interrogations of high commanding alien leaders pinpoint the location of the alien operations to a subterranean base located in Cydonia on Mars. By 2002, a ground assault on Cydonia using an ‘Avenger’ alien-human hybrid battlecruiser results in a human victory. The alien “brain”, ironically the controlling entity of the alien forces, is only just destroyed by X-Com forces after fighting fanatically through hordes of aliens protecting it. In the death throes of Cydonia a desperate dying signal was sent. Its location: Earth.
2002-2005
The last vestiges of the aliens are hunted down and destroyed without the guidance of the alien super leader. The initial signal beamed to Earth from Mars is now thought to have been a desperate plea for alien bases on Earth to send reinforcements.
2013-2038
By 2013-2038 the whole world is suffering from economic depression. Countries rise and collapse, 'Elerium', which was the 'super fuel' used by the aliens and also thought to solve the problems of the Earth is in very limited supply. X-Com is disbanded, and old bases become theme parks, historical monuments or museums. The last 'Avenger' spaceship which failed to scan for any more signs of Elerium-155 on Mars is sold to the Smithsonian Institute. Cults to the aliens rise such as the Cult of Sirius and counter religions such as the Inquisitors give way to mass battles under jihads. Large countries annex poorer ones, still having their own economic problems to deal with. By 2027, there are only sixteen widely-recognised world governments.
2039
A wealthy software tycoon, F. Denman Williams, purchases one of X-COM's aquatic stations. Fearing that the alien crisis is not yet concluded, he also hires the base's full complement of staff, both military and scientific. Dubbed S.O.R.E.S.O (Sub-Oceanic Reconnaissance and Extraterrestrial Salvage Operation), the organisation resumes X-COM's old duties, cataloguing UFO crash sites beneath the seas - and hunting down Elerium-115 stockpiles.
During this time, horrific attacks on many kinds of boats, vessels and cruise liners at sea are happening. Some civilian aircraft are also attacked and downed in the ocean. Across the world, surface vessels, aircraft, and submersibles begin to vanish without trace. These events steadily increase in regularity, and in response to increased public hysteria scientists release theories based on natural-magnetic anomalies, freak storms and more being responsible for the disappearances, ignoring reports of unusual submersible vessels at the problem sites.
Tabloids once again take the lead in declaring that Aliens are responsible, and the resultant public outcry calls for X-Com to be reinstated. The governments of the world ignore these calls to arms. S.O.R.E.S.O., still active after many years, steps up it's readiness to an all-time high. Many underwater crash sites still remain to be searched, but occasional missions are dispatched to investigate disappearances. No signs of alien activity are discovered, although the response time of S.O.R.E.S.O.'s craft is over two hours.
The S.O.R.E.S.O. craft 'Khimtar' is lost whilst investigating UFO crash site 137 near the wreck of the Titanic in the North Atlantic. It implodes and sinks under mysterious circumstances. The last words of the vessel's skipper are discovered nearly two months later, in the form of a distress call to the Pentagon. The message concludes with the prophetic words "I think they're back."
2040
Establishing relations with the British Hydrospace and Sub-Am corporations, S.O.R.E.S.O initiates testing of the newly developed 'Barracuda'- and 'Triton'-class submersibles.
Despite a high initial failure rate - some faults resulting in the death of personnel - the bugs are eventually ironed out. Several of the craft are leased out. At the same time, the governments finally action, recruiting soldiers and training them in aquatic combat. Several of the few surviving X-COM personnel are also recruited to train and organise the new soldiers. With startling ease, the government assumes command of S.O.R.E.S.O , utilising their main base as X-COM's new base of operations.
Within days, Ocean Base 1 receives a distress call from the British passenger liner 'Hyperion'. One of the new 'Barracuda' subs is sent to investigate. Upon arrival, only a broken wreck is discovered. The pilot, Jake Burton, steps from the sub to investigate, and within seconds contact is lost. A second team sent in later determines that the craft was sunk by an unknown weapon. No trace of Burton is ever found.
2041
January 1st: The Second Alien War officially begins.
Sightings of the strange new submersibles continue, and it rapidly becomes apparent that alien forces are once again at work. Alien activity escalates as the aliens once again seek to terrorize major metropolitan areas, this time focusing on coastal regions. Some species, such as the ‘Aquatoids’, are reminiscent of the previous alien invaders, whilst others are entirely new and utterly strange.
The 'Barracuda' submersibles prove highly effective at intercepting the smallest alien craft. However, the ground (or sea-bed) X-COM forces are sorely lacking in equipment with which to combat the aliens. Due to the severe lack of Elerium-115 to power plasma technology, and with the discovery that the laser weapons cannot be adapted for undersea use, the first aquanauts are forced to rely on archaic and primitive weapons. Research into the weaponry used by the aliens is rapidly initiated, although more indicated research begins in improving the old Plasma technologies for underwater and land based use via alternative power sources and ammo. The result is Gauss weaponry, and proves effective against the aliens so far.
2042-2045
The war continues, furious and unabated. Still more alien classes are discovered, and one that sternly remains within every X-COM soldier's mind is the "Lobster Man", an almost indestructible alien super soldier. These super soldiers are practically immune to normal Terran weaponry including the newly introduced Gauss weapons.
An alien substance known as "Zrbite" is discovered to be virtually analogous to Elerium-115 in its uses. It powers most alien equipment and weapons. It is also discovered to be dangerously reactive and unstable, but deemed within acceptable safety margins considering its uses in replicating alien technology. It is part alien bio material and part gold in origin.
The result of the recovery of equipment and aliens (dead and alive) from downed alien craft brings the fruits of advancement, and not too shortly either. Sonic weaponry is finally refined for X-Com use and proves highly effective against the invaders. Rotating close combat titanium weapons known as ‘Vibro-Blades’ are found to be in the possession of some of the humanoid aliens, and are able to withstand the pressures of the deep while maiming enemy forces. These weapons are quickly researched and adapted for X-Com use.
Water tight armour is also researched, with more refined suits protecting X-Com aquanauts against the alien foe.
This is also the turning point of the second alien war. Heavy alien infested areas under the seas are contested by X-Com and alien troops, sometimes mounting to full scale war.
*T'leth is the name of the Alien's city/colony ship.
Also great thanks to Elerium!!
, damn was it fun 
