Event | Synopsis | OST | Trivia |
The following pertains to a subject that is not yet released in the Global server of Arknights. |
Following the Site 359 incident in Trimounts, Lone Trail is the first attempt in the current Terran civilization to explores the beyond of its "fake sky," featuring the "Project Horizon Arc" launched by the Columbian military as part of their greedy arms race that will soon be hijacked by Rhine Lab to fulfill Kristen's lifetime goal. Along with that, it reveals some of the most hidden secrets regarding Terra's true nature, especially the Doctor's "race."
To Infinity...[]
A Thousand Suns[]

The "Project Horizon Arc" is about to complete, but with Kristen fooling around, it too might bring utter destruction onto Columbia's glory.
A month ago, the Site 359 incident almost created havoc in Trimounts, but everything seems right under control in its aftermath... until Kristen Wright suddenly disappeared without a trace half a month later. Not only she hid herself so deep that no one could ever find her, but she even severed her communication with the outside world. Only a handful of Rhine Lab seniors knew her whereabouts, but were strongly reticent about the secret. The whole of R.L. suddenly fell into panic, prompting Saria to hurry back to Trimounts.
But perhaps the one who was more anxious than the rest is the Columbian Department of Defense. For two years ago (Terran year 1097), Kristen had been secretly collaborating with the DOD to conduct the Project Horizon Arc – a massive superweapon program that could easily surpass every Terran nation. Under this project, R.L. and the military have built the Arc-0I, a ring-shaped floating station launched by its energy source, the S.H.A.F.T., which will then send out laser beams upon its target in mid-air through its focus generator, the H.A.M.H.R.R. However, with Kristen having gone missing just before its official launch, the local military feared that Kristen could foolishly use such destructive weaponry against the country. So, Blake the "Colonel" and Ferdinand Clooney, who sought temporary refuge in the DOD, vow to stop its launch before it brings utter destruction to Columbia.
Meanwhile, Dorothy's Transmitters were all lost following the lab's clean-up. Dorothy had been worrying that such a material could fall into the wrong hands, especially since the Hub was already destroyed, making them hard to track down. Under her request, Silence secretly infiltrated the RL headquarters to search for clues regarding the missing Transmitters.
In the midst of the panic, Rhodes Island chose to become involved for the sake of peace. Kal'tsit feared that Kristen might have obtained some lost, ancient technologies that would allow her to accelerate the project but could potentially be misused if she so intends. She brought the Doctor and Ifrit along her side, and she sought cooperation with both Saria and the Maylander Foundation through the Tin Man to stop the crisis. Surprisingly, Rosmontis is present with the gang as well. She received a letter from Loken Williams, the mad scientist who was responsible for her demise, in hope of meeting her again. Deeming that Loken could have been bailed out from his prison by R.L. to aid Kristen's Project, she hoped the two could meet again to settle their unfinished past once and for all.
Shooting Stars[]
Before the official launch, there was a small test flight for the prototype H.A.M.H.R.R. around the mobile plate where the Arc-0I was built. However, a malfunction caused the aircraft to crash onto a section of Triton Factory. Believing that the site is where Kristen was hiding, the Union Army soldiers have the site and the surrounding areas locked down. Meanwhile, Silence has successfully infiltrated the area amidst the angry crowds. But to her surprise, Saria too is present in the factory together with the Tin Man, and her suspicion on Saria grows greatly. As she continues her search, she meets Jara, the director of Rhine Lab's H.R. Investigation Section, who assisted her in searching for the lost Transmitters through her new outfit built with the Transmitters' sensory devices. The Transmitters' eventually lead her to Parvis' lab, but the mentor and former disciple do not speak much as the latter questions the former's involvement in this incident.
Back at R.L., Saria and Kal'tsit are sharing intel regarding the most recent experiment where Kristen could have been involved. But a sudden ambush by the Union Army soldiers destroyed most of the documents. Surprisingly, the Doctor encountered Muelsyse and the two agree to work together to track down Kristen. Even then, Muelsyse seems to be hiding her real intention from them.

The majestic, furious clash between the Elf and the Kukulkan, two lonely races upon this land.
Ho'olheyak, the agent of Maylander, had been manipulating every side from the beginning. By using the air crash in the Triton Factory, she lured everyone so that they would not easily search for Kristen's hideout. In fact, she had a deal with Kristen as part of their collaborations. Whenever the Arc-01 is completed, she would give Ho'olheyak her source of knowledge from an unknown "god," a being from the forgotten past. The Kukulkan is indeed ecstatic by such news as she yearns to regain the truth of her ancestors in order to revive their true form in the ancient era.
On the Army's side, Ferdinand has been a major obstacle to Blake and his company and Ferdinand is upset by the soldiers' extreme methods; in fact, it is revealed that he was never loyal to the soldiers. To him, he cares about R.L. more than the rest the directors through his earnest endeavour, but fears that Kristen's experiment will lead the company he loves into the verge of collapse. While Blake has attempted to persuade Ferdinand to fully join the Army's side, the latter stubbornly refuses out of his loyalty to R.L.
The Great Halt[]
A few days later, Conrad Jackson, the current Vice President of Columbia, makes a visit to R.L. as part of his campaign for his election, surprising everyone in Trimounts amidst the confusing chaos. While R.L.'s tightened security had ensured his safety, danger is still looming around. As part of the deep political struggle between the Federal Government and the DOD, Blake feared that the Vice President will become a threat to the Project Horizon Arc if he meddled in, hence dethroning the Union Army from their former glory. The soldiers planned to assassinate the Vice President by splashing acidic liquids on him, but they were easily suppressed by Maylander's agents and the Doctor's gang. Even Ferdinand stepped in by sending several power armors to halt the soldiers from tarnishing R.L.'s name. Desperately, they destroyed liquified Originium pipelines as final resorts but utterly failed. The Vice President is safe and sounds thanks to Jara's intel, and she promised him that the headline tomorrow would not be the repeat of the Triton incident.
While Ifrit was stopping the Army from harming the Vice President, Silence and Saria finally met again. Silence ushered out her grudge onto Saria for her questionable involvement. But before Saria could decide to reveal the truth, a sniper of the Army severely injures her head, bringing her into unconsciousness. Nevertheless, Silence and Ifrit helped carry Saria while fleeing from the Army's pursuit.
Meanwhile, the Union Army's target is not only the Vice President as The Doctor and their company were fending themselves from the soldiers through the aid of both Muelsyse and Justin Jr., the director of Rhine Lab's Business Section, who lured them away. In the midst of the escape, Loken encountered Rosmontis for the first time since his release from the prison. His presence brought utter disgust to the Doctor, and caused Rosmontis to somehow recall her upsetting and painful memories. Yet, Loken did not fight back, but before departing, he gave her the address where he claimed to be his final "court."
Down in the deep alley, the Tin Man was on his way to regroup with Saria and the rest following the failed assassination. Ho'olheyak approached him and openly declared her desertion from Maylander. To the Tin Man's surprise, he was trapped by both Ho'olheyak and Nasti Lundrey, the director of Rhine Lab's Engineering Section, with the latter having used her oral Arts of the Banshees to freeze his movement. As her "farewell" to Maylander, she has Nasti to burn him away through her Arts, the only remains being his cyborg body. With her senior "being dead," Ho'olheyak could now focus more on fooling the Vice President and halting the soldiers' advance.
...and Beyond[]
Confessions Before Departure[]

Putting down the grudges of the past, Saria and Silence head on for a common goal.
Blake and the soldiers were almost driven to madness due to their failure, and Ferdinand seemingly intended to use a threatened Jara to reveal Kristen's hideout through her relationship with Maylander. Just then, Silence volunteered herself to both sides by injecting the Transmitters into her body, hence becoming a "Hub." As they follow Silence's tracking, they were greatly dumbfounded by the fact that Kristen's hideout was actually in the city's enormous junkyard covered by anti-Arts detectors, and the wastewater pipelines that run through the yard seemed to be energy siphons from the S.H.A.F.T., which was currently under the Army's control, to the H.A.M.M.R. Just the soldiers were about to land onto the junkyard, they faced tornadoes created by Ho'olheyak's Arts to delay them before the launch. Even when Saria personally breaks her way to the H.A.M.M.R. by taking down Ho'olheyak, she is too late to stop its launch. Nevertheless, Saria and Silence met again briefly and head on towards their own goal while promising each other to survive the chaos for the sake of truth.

"My dear Narcissa, forgive me for turning you to such a failure....and may you cast your judgement onto this filthy man"
Meanwhile, the Doctor, Muelsyse, and Rosmontis were passing through the underground passages leading towards the H.A.M.M.R., but Loken blocked the two away through a wall to have a reunion with Rosmontis. Loken confessed his sin by turning her into a war machine due to the Army's pressure despite his genuine love for the girl, yet he blamed himself for making her into a failure, mourning that he could have moulded her into a perfect being, a powerful non-Infected Arts user. All he yearned is to have her sentence death onto the frail old man as his final judgement while bringing him away from the suffering of his sin and his terminal illness. Rosmontis slowly regained her memories bit by bit, and fuelled by vengeance, the Feline went berserk by brutally crushing the approaching soldiers through her psychic Arts. Fortunately, Ifrit arrived to calm her down, proclaiming that Rosmontis was not alone through her newly found family. Upon settling down, Rosmontis decided that she has to face her own past alone.
When the Doctor and Muelsyse finally arrived at the H.A.M.M.R., he saw a replica of Muelsyse's ecological garden, and to their utter dismay, the lab is actually powered by a Sarcophagus. Suddenly, Muelsyse parted away from the Doctor by gushing him out away from the lab through her water "magic." She bided farewell to them bitterly, and she embarked her journey to follow Kristen's voyage as part of her goal to search for unpolluted habitats for her Elven tribes. As the H.A.M.M.R. is about to launch, Kal'tsit brings the Doctor away from the rumbling through Mon3tr and lead them to their newly discovered "site."
The First Launch[]

The blaze of the first "spacecraft" brightens the sky above Trimounts, leaving a remarkable memories to everyone.
November 22, 1099, the night sky of Trimount was suddenly brightened by the combustion of Arc-01. Now, the DOD and the Federal Government had to form an uneasy alliance to take down the hijacked station at all cost. Military aircrafts fired their missiles endlessly onto Arc-01, but it only keeps on lifting up. The soldiers attempted to cut down its energy in the S.H.A.F.T., but to their horror, not only it keeps on charging, but the meter has gone beyond its energy readings. Upon reaching 5,000 meters above sea level, however, it stopped and recharged its energy from the ground. Deeming it to be the only way to take down Arc-01, soldiers risked their lives in high-altitude flight to land onto the station.

Saria is Justina executing her justice to bring all things to order, whereas Ferdinand is Prometheus who "steals" the knowledge of the sky for the people.
Saria and Ferdinand followed suit, and upon their arrival, the two scientists were shocked by its latest technologies far beyond that of known Terran civilization. From the very beginning, Project Horizon Arc was simply a ruse to fool the DOD. What Kristen aimed for was actually her lifetime goal: to go through the "fake sky", or the "Barrier" coined by academics or "Starpod" by poets, that sealed off the Terran planet by 6,152 meters above sea level. In order to penetrate the Starpod, it requires an enormous amount of energy that could have powered every nomadic city on Terra, and Arc-01 was specifically built to withhold such energy through the miraculous hands of Loken Williams. However, if it succeed, there is simply no way to return to the ground. Saria headed on to stop Kristen's "suicide" while Ferdinand stayed back to both witness its magnificence and hold Blake and the approaching soldiers.

"Silence, you can't just shoulder your own burden by yourself ALONE!!"
After persuading Jara to step aside, Silence continued her search for the Transmitters hidden in the S.H.A.F.T. Upon reaching the laboratory, she saw Parvis experimenting with the Transmitters while slowly merging with them. As part of the project, Parvis has been using the Transmitters' Hub as an anchor point so that Arc-01 will precisely penetrate the Starpod's weakest layer. In the meantime, he wished to use them to fully accomplish his Chimeric Experiment, the ultimate goal of "merging" the minds of every living being into one collective consciousness mimicking the Sarkaz Nephesh. Silence forcefully destroyed the 'Hub', but Parvis had already been turning himself into one of it to replace the damage and lost his consciousness as a result due to its side effects having eroded his nervous system, leading to his grand sacrifice for the sake of science. Silence blamed herself in tears for both unintentionally taking away the life of her mentor and failing to stop him, but Ifrit, who coincidentally met her in the lab, woke her up through her scolding in which she should not just put the burden of her past on her own shoulders. Silence thanked Ifrit for her words and proceeded to escape from the collapsing structure.
To the Borderless Hades[]
On the Doctor's side, they were heading towards an ancient underground ruin beneath Trimounts which Kal'tsit believed to be the source of Kristen's project. While they came under Ho'olheyak's harassment, the undead Tin Man finally showed up to have a showdown with her. With that said, the two continued their journey towards the ruins.

Filled with many Sarcophagi, the Hall of Stasis is more of a graveyard for a long forgotten past.
To the Doctor's bewilderment, The ruin was filled with numerous Sarcophagi dumbfounding his thoughts – the ancient device they were woken up from back in Chernobog, and inside each Sarcophagus is a human being resembling them. However, their arrival woke up the "god" of the ruin: Trevor Friston the Preservator, a dying human-like artificial intelligence hailing from the ancient previous civilization. For millennia, he has been guarding them alone while hoping that those inside the Sarcophagi will awake and rebuild their civilization, but his loneliness has led to his desperation. Seeing that there was no hope to wake them up again, he sacrificed himself by revealing as much knowledge as he can to Kristen. In turn, the Sarcophagi will act as the "Hall of Stasis" for Arc-01, an alternative powerhouse built beyond the knowledge of Originium Arts, hence allowing Arc-01 to unleash lasers that penetrate the Starpod whilst fooling the Union Army from severing the energy source.
While being surprised by the Doctor's presence, he was still puzzled that whether Kal'tsit and the amnesiac Doctor have the will to carry the burdens of the predecessors. With that said, Friston used homographic displays to test the two of them. The Doctor was given a chance to reexperience their past, including meeting a hologram of Priestess and witnessing the Chernobog Crisis, yet they stood firm amidst the chaos while facing dilemma. Meanwhile, Kal'tsit has to recall her immortal mission to protect Terra and its people from self-destruction. Despite carrying such a mission alone, the Preservator believed that sometimes, she had to entrust it to her comrade, her faithful helping hand, to finally accomplish her goal.
As the test comes to an end, Friston wished Kal'tsit to "delete" his millennia-old memories to reborn and experience a new life on Terra. And before that, he revealed some essential information to the Doctor, especially regarding Originium. From his words, Originium was related to Priestess as part of her "mad beginning," and that it was originally an essence to bring blessings to Terra that soon went haywire. Even then, Friston did not reveal much but wished them good luck in finding the truth in the future.
Good Night, Terra[]
Stars Beyond the Skyveil[]

The Land reaches its peak to reach the Star, but the Stars flies high to gaze beyond the Land.
Saria fought her way bitterly to the Galleria Stellaria – the heart of Arc-01 — while withstanding the weightless environment. Under the glittering stars recreated by the hall, Saria and Kristen finally met again for a final showdown. Together with the "Perturbation System" that replicates the stars' orbits, Kristen proves to be a challenging foe despite Saria's calcification Arts. Yet, Saria wanted to bring Kristen back to the ground as she believed her "suicide" will only bring disaster onto Terra. Nevertheless, Kristen deemed that time is indeed running out for the Terran civilization. However, just before Saria could bring her back, Kristen fooled her by pulling off the emergency exit just right beneath Saria.

After endless ages forgotten by the present, the true face of the sky has finally unveiled.
With disturbances now gone and energy fully charged, Arc-01 fired a powerful laser beam to penetrate the "fake sky." As it burned off the barrier, aurora-like shockwaves scattered across the Terran sky, forming a miraculous phenomenon to every Terran that gazed above. Most of all, the true nature of the sky has finally revealed. Along with a starry night filled with observable stars, something that has not been achievable for astrologists for millennia, there comes the Twin Moons of Terra — one of which appearing more like an artificial satellite that seemingly observes lives below. This was the first time in Terran history where they were now so close to the ancient truth of its predecessors, and the event, the "Trimount Arc," would soon later be archived by later generations to come, whether for science or for praises.

"The sky.....is indeed more beautiful than my imagination."
Upon accomplishing its final mission, the Galleria will soon break off from the Arc-01 in its 2nd staging to continue its aimless journey in space with Kristen inside. Even Muelsyse was separated from the Galleria despite Kristen's promise. As the Arc-01 disintegrates, Muelsyse used her water "magic" as cushions to save various personnel falling from above. Saria survived the high-altitude fall thanks to her calcium shield, and together with Silence, they gazed above onto the starry night while standing in awe of such "unnatural" scenery.
Truth for Loners[]
Following the Doctor's departure from the Hall of Stasis, Ho'olheyak quietly sneaked into the ruin to seek for her own truth after escaping from Maylander's pursuit. Venerating the dying Preservator as her "god," she yearned for his "omnipotent" knowledge being blessed onto her, but the "truth" she finds is beyond her imagination. Thanks to her staff, Friston's consciousness survived the deleting process, and she casually handed it to Kal'tsit instead of the Tin Man and Maylander.

"Mark my words; I, Mark Max, President of Columbia, will become the Sword and Shield of Terra and the greatest hero upon this land!!!"
Despite the threats, Maylander received an order from the President of Columbia to spare them and quietly retreat. Without Kal'tsit's knowledge, they have been supervised by President Mark Max, the super A.I. that runs the country behind the scene. While he put high hope on R.I. to "revive" Friston, his "father," he also openly declared himself to surpass the "Preservator" by becoming Terra's "sword and shield," agitating Kal'tsit to destroy his surveillance cameras.

The two loners on Terra seek comfort from each other deep within the calmest lake.
Upon returning to the ground, Doctor temporarily departed from the team and heads toward the crashing site of Arc-01. There, they find a body of water forming around the ecological garden. Out of sorrow, Muelsyse decided to end her life by dehydrating herself with her water "magic" and turning herself into a lake, a fairy-tale like ending to the lonely Elf. Nevertheless, they risked their lives to save her from her demise, and promised her that they will always be on her side.
Rosmontis eventually met Loken for the "final judgement." The mad scientist hoped that she would put an end to his miserable life and fulfill her vengeance. Yet, Rosmontis refrained from doing so, knowing that doing such an act will dirty her hands. Even then, Loken was grateful for Rosmontis to be with him in his final moments, and Rosmontis declared that she would forever erase him from her memories.
A Sweet Dream in the Void[]
Days after the "Trimounts Arc," R.L. has to reorganize its structure due to Kristen gone "missing," Parvis' death, and Jara's official retirement. Despite the difficulties ahead, the future of R.L. will definitely shine bright. Ferdinand was pardoned by R.L. for his wrongdoings in the past, and he proceeded to spread his knowledge regarding the Terran sky to the science community. Saria succeeded Kristen's position as R.L.'s next Control with Silence being her secretary. Most importantly, Silence published the "Trimounts' Joint Declaration of Scientific Ethics," and she hoped that it would set a standard for ethics of the science community and prevent disasters and wrongdoings of the past from repeating.

Good night, Kristen Wright; may we meet again in the endless void.
After five days of wandering in space, the Galleria was about to shut down due to the lack of a sufficient energy source, and Kristen had to lay down inside the Sarcophagus reverse-engineered by Loken. As she undergoes cryogenic sleep, she recalled the two greatest moment in her life: one is the day when she brought Saria back to her hometown to elaborate her lifetime mission to uncover the "fake sky", and the other is her finally fulfilling her parents' goal. With that said, she bid farewell to Terra and forever shut herself in the deep void, waiting for future generations to follow her pioneering footsteps.
“ | If for millennia to come, our descendants have sailed along the stars, they shall greatly exalt her name. | ” |
—An epithet to Kristen Wright |