Author's Note: Hello readers! I'm here with a new story for a XCOM/Mass Effect crossover! Now, this story is inspired by a lot of other XCOM/Mass Effect stories out there such as XCOM: Second Contact, Once Bitten, Twice Shy and among others. A such, you will find some similar plot elements (such as what happens to human after the Ethereal War and Turian Contact War and the like). However, I will be adding my own story elements to make it interesting.

This story also has its own prequel, titled XCOM: Shattered Past, chronicling the first generation of XCOM's trial during the Ethereal War if you guys are interested to read. However, the story is written at the same time as this one and which one I will update depends on my muse and mood so…

Prologue – Enduring Legacy

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"Those who play with the devil's toys will be brought by degrees to wield his sword."

-Buckminster Fuller

A blue ethereal energy can be seen floating above the planet Earth as if waiting for something. From a distance, it was easy to mistake it for an anomaly in space. However, it was not an anomaly and in fact, it was very much alive.

The blue energy was an alien known as the Ethereal to humans. The alien was from the very same species that had inflicted so much pain on the planet below and its inhabitants. Yet, this Ethereal…was different from the rest of its species.

"Humans…flawed, yet there is so much potential in them. However, in order to harness their true potential, they need to grow on their own. Enough damage in the name of guidance has been done to them by my brethren," the Ethereal, Asaru mused.

On 1962, mankind experienced their First Contact with alien life forms. Unfortunately, it was hostile and lead to war between humans and the invading alien species, whom the humans called The Outsiders. Against all odds, mankind won and managed to drive The Outsiders away and at the same time, kept the whole ordeal a secret from the rest of the world.

However not all aliens were driven away from Earth at that time. Asaru, who was one of the key players in the ordeal, decided to stay and help mankind to prepare for the coming of his brethren.

And come they did. On 2015, his brethren and their slaved alien collective assaulted Earth. The Second Contact proved to be much more destructive and their effect was permanent. Unsurprisingly for Asaru, mankind won. He expected as much, after all, he had lived with them for half a century. He knew them better than his brethren ever did.

However, mankind's victory would be temporary if he didn't intervene for perhaps, the final time. After all, the Uber Ethereal that assaulted Earth was but a piece of a whole. Mankind, as of now, would not survive the full might of the Ethereal Collective.

The Ethereal concentrated his psionic powers and soon, purple aura began to envelop his being. A few seconds later, the psionic cocoon flashed brightly and disappeared in a purple light.

Asaru emerged in a purple flash of psionic energy somewhere outside of the Solar System. In front of him was a huge starship, easily ten times the size of the Temple Ship on Earth. This was the Ethereal's true base.

Asaru then slowly flew towards the ship, contemplating on what he would say to his brethren. Their species unique in that it was divided into two sides. One side was the Ascended and they are the Ethereals that decided to discard their need for the physical plane such as technology and their own bodies. This grants them their pure energy form and strong psionic powers.

This freedom from physical needs and constraints also granted them a different mentality. They do not need to be part of a psionic hive mind or collective for the sake of increasing psionic powers since, they are already strong enough without it. As such, Ascended Ethereals have their own unique individuality. Most Ascended Ethereals made it their mission to help and uplift other species, albeit in a more benevolent and subtle manner as well as without the use of technology.

Although Ascended Ethereals can live forever, they were not immortal. Despite their form, they are incredibly weak without a host and can die from something as simple as a gunshot, as what had happened to Shamash, another Ascended Ethereal.

The other side of the Ethereal species was the complete opposite. They simply called themselves Ethereals. Realizing the weakness of the Ascended form, they rejected it and strive to achieve perfection in both physical and psionic form. It was this drive that made them search for the 'ultimate' species.

And it was this drive that made them cruel and ignorant to the other species that they encountered.

However, Asaru could not bring himself to truly hate his brethren for what they did. They didn't do it entirely for their own selfish need but they were also driven by another force that was far stronger than them.

The Old Ones.

Asaru reached the ship and its inhabitants of the slaved species turned their attention to him. They didn't do anything however and bowed in fear and respect. Despite the form, they can still recognize an Ethereal. That and his brethren did not wish to end him just yet.

He effortlessly made his way into the center of the ship, where the entire collective of the Ethereal were located. Inside the room, there were thirteen Uber Ethereals surrounding a giant translucent orb filled with psionic energy or rather, the Ethereal's collective minds.

"Ah, Asaru," one of the Uber Ethereal spoke, but it might as well be the entire Ethereal that spoke to him. "We figured that you'd be involved with the New Ones somehow,"

"Yes, although I have been involved with them for much longer than you had," Asaru replied.

The Uber Ethereals laughed together. "And what was the result? Half a century with them and yet, nothing! But We, We have accomplished far more in such a short span of time than you have!"

This time, it was Asaru's turn to laugh. "Are you sure that I have achieved nothing? Surely that you didn't think that their aptitude for The Gift is just a coincidence?"

The Uber Ethereal was silent but Asaru could feel their glare at him. "What have you done with the New Ones?"

Asaru smirked. "What have I done indeed?"

The Ethereal Collective growled. It wouldn't do well for them if the New Ones' psionic strength or Gift were only because of Asaru. For all they knew, only those that Asaru had interacted would have psionic capabilities and the rest were…useless.

After extensive research on the humans, they found out that not all humans exhibit the potential for psionic capabilities.

"However, I have valuable knowledge I wish to share with you. Knowledge that would change everything," Asaru said and the Ethereal was silent again.

"The Gift isn't just about the physical form, or even mental, but rather the essence of the individuality," Asaru started. "The Gift can be embraced as well as rejected and it is why most of the humans you have studied so far showed no aptitude for The Gift,"

"Are you saying that those humans rejected The Gift?" The Ethereals asked.

"More like they did not know that the Gift was possible to them. Don't you find it strange that the one with the strongest Gift was with the resistance force, and not the civilians?" Asaru answered.

"The XCOM as the New Ones called it," An Uber Ethereal stated.

Asaru nodded. "They were exposed to the concept of the Gift and subconsciously wished it for themselves. Now, what would happen if they were to…reject it?"

"Preposterous! If it was so easy to embrace the Gift, we would have found the perfect specimen a long time ago! And yet, only a select few have them!" The Ethereal Collective said in almost a scream.

"That was because of your own doing," Asaru said calmly.

"What?! Explain!" every Uber Ethereal spoke in anger.

"Think about it, the Sectoids have the Gift because they have the brilliance to comprehend it and wished it for themselves. Your loyalist Thin Men have the brilliance to understand…and fear it, hence they rejected it. Their loyalty to you is more of fear than anything else," Asaru explained and he could feel the glare from the Ethereals again.

"The Mutons…you were so eager of their potential, that you tested them too early. They were only cavemen, barely intelligent enough to count past their toes when you descended upon them. As a result, their growth as a thinking species capable of embracing The Gift was stunted. As for the rest, the ones that were more mechanical than organic…in your drive to eliminate the weakness of the organic, you deprived them of their higher thoughts and thus, their capacity for The Gift," Asaru stated.

"The other races," Asaru gestured to the door behind him, indicating the slaved alien races. "Have the potential for The Gift…but it is your own doing that denied them that,"

"LIES!" the whole ship shook and Asaru shuddered as well.

Asaru sighed. This was why he couldn't truly hate his brethren. They were misguided, yes, but with good intent. They were afraid of the Old Ones and wanted to prepare the other races to face them. They believed that in order to do so, one must have the right physical and mental aptitude. In their search, they've wronged other races, that was true, but they believed that those species would fared better under their Collective than the Old Ones'. And they truly believe that once they have found the perfect specimen, it would be their salvation and vindication for what they have done.

Unfortunately, they also believed it was their burden to face the Old Ones. Thus, when they have found the perfect specimen, they would not ask them to face the Old Ones, but instead, they would take the number of bodies required to face the threat.

"The fault is not entirely yours but mine as well as the others," Asaru said, referring to the other Ascended that ignored their Ethereal brethren's actions. "And so, I would not turn a blind eye again. I've come with an advice; leave the New Ones alone,"

The Ethereal Collective was silent and Asaru took this chance to continue.

"If you claim them now, you would only destroy any potential they have. You've done enough for them. Instead, let them grow on their own. Let them expand their minds and soon, the entirety of the New Ones will be able to embrace The Gift. And when they have matured, only then I suggest you approach them, politely," Asaru said and the Ethereal Collective laughed.

"Do you think they would just easily accept us? After all we have done to them?"

Asaru smiled. "When the right time comes, yes. Besides, humans do not like to be forced to do something against their will. If you force your will…your Gift against them when they have their own…" Asaru let the implications linger.

"Instead, if you cooperate with them…imagine what could be accomplished! An Ascended with an Awakened Human!" Asaru said rather excitedly. The rest of the Ethereals doesn't seem to share the sentiment however.

Asaru pushed on. "I have shared bodies with a lot of humans even before they were aware of the Gift. You've heard of the New One's first contact, correct? Of what I and a handful of humans managed to accomplish…"

The Ethereal Collective was silent as they contemplated the thought. They've known about humanity's first contact. At that time, Asaru used a human as his host (without the human's knowledge) and fought against the invasion. That Asaru and the human became a one man army and was almost unstoppable.

They have also heard of how Asaru's host threatened to not only destroy himself, but other human resistance when he learned the truth. Just because he refused to be a 'slave' to others.

Humans are stubborn. The New One's action proved that. Perhaps Asaru had a point?

The silence continued and Asaru knew that his message has been made. "I've said what is on my mind and so I will take my leave. Farewell, my brethren," Asaru said and disappeared in a psionic flash, leaving the Ethereal Collective to their own thoughts.

Then, an Uber Ethereal raised its hand and a holographic model of Earth appeared and The Ethereal Collective could only stared at it in silence.

…

...

XCOM Database

Note: Most of the records from the old XCOM Initiative of 1962 has been heavily redacted and no unedited copies are available. As such, many crucial information such as dates are not available and made the entire file, vague at best.

- The First Contact War

On 1962 [exact date unknown], Earth was attacked by extraterrestrial aliens called The Outsiders. The Outsiders wished to invade and conquer Earth and began their campaign with the United States as their first target. In response to the invasion, the United States activated the XCOM project which originally was created to combat the threat of communism during the Cold War. The XCOM project then changed its purpose to combat the alien threat, acquire their technology and erase the fact that the alien invasion ever happened in the first place.

After 3 months, the XCOM Initiative managed to fulfill its objective with great effect, especially in erasing the truth of the invasion to the point that when the second alien invasion (The Ethereal War) occurred 50 years later, the public believed that it was the first. Only with the reveal of the XCOM Initiative to the public (after the Ethereal War) and the digging of old files did the truth was revealed.

The reveal of the First Contact War served to increase XCOM's popularity, although some speculate that it was a propaganda by the XCOM.

- Ethereals

During the First Contact War, a collective of alien species was involved in attack against humanity. Although most of them were used as foot soldiers and their impact to the war was minimal at least, one alien species in particular was the key component in the war. The alien species was the Ethereals, a creature made of pure energy and capable of psychic feats known as psionics. The Ethereals are incredibly powerful in regards of their psionic capabilities, however, they are weak physically and can be killed with a single bullet or even a knife.

In the course of the war, only two were encountered and played key roles in the war. The first was Shamash, which was used to power the Outsider's command network system called the Mosaic. The second was Asaru who sided with humans and used an XCOM agent as a host. This wasn't known until late in the war however.

An Ethereal with a symbiotic relationship with a human host can result in a powerful being. The Ethereal's weakness is reduced to a certain extent (their physical strength depends on the host) and the human host gained psionic powers. However, it is unsure of who is in control in this relationship. With a limited recorded case of the symbiotic relationship, it is not possible to make sure as of right now.

However, during the second alien invasion or The Ethereal War, it is revealed that there are two subspecies of the Ethereal race. The first is the Ethereal in pure energy form called the Ascended Ethereals. Fortunately this subspecies of Ethereal is not many, chose to act alone and are rather benevolent if, their action is to be believed.

The second subspecies is known as the 'normal' Ethereals. They prove to be the complete opposite to their Ascended counterparts. They have an atrophied body (their original body), which made them more resilient, their numbers are more numerous and they are malevolent in nature since they are the mastermind behind the second alien invasion.

The intent of both Ethereal subspecies mirrors each other but with different result. The Ascended Ethereals wish to uplift alien races in a less direct way and the 'bodyjacking' of the uplifted species is not their end goal. The Ethereals however, forcibly uplifts alien races and once a suitable race has been found, they would seize control of their body.

Author's Note: Alright, hope this one managed to snag your interest! Read it and tell me what you think!

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