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"The future of humanity will always be decided by us humans." ― Yu Ominae[source]

Yu Ominae (御神苗 優 Ominae Yū?) is the leading character of the Spriggan series. He is a top-class agent of the ARCAM Private Army, a military arm for the ARCAM Corporation that is an international organization devoted in protecting the ancient civilization's legacy from adversary forces who seek to abuse them for their own benefits. He is stationed at ARCAM's Japanese Branch and is often called upon by ARCAM to carry out missions related to their philosophy. Outside of his duties as a Spriggan, he is also a high school student.

Yu is voiced by Shôtarô Morikubo in the OVA and game adaptations of the manga. In the English dubbing of the former, Chris Patton provides the voice. In the ONA, Chiaki Kobayashi plays the character, while Kyle McCarley voices him in the English dub.


Yu is of average height for a teenager with a thin, but well muscled build. He has short, spikey black hair and brown eyes. When attending his school duty, Yu usually wears gakuran high school uniform as his daily attire. He also wears a pair of various casual t-shirt (with sleeves in winter session) with fabric trousers or jeans during his off days or missions in Japan. During his duty as a Spriggan, he wears an armored muscle suit made out of an Orichalcum material that is developed by Dr. Mayzel. With the suit, he wears a tactical vest on it, a pair of power gloves, and a protective head gear that exposes his hair. He is also usually seen wearing a bandana on his forehead and have bandages on his face from physical injuries.


"Maybe I'm just being sentimental, but my only connection to "normal society" is at school. If I go neglectin' it, then I'll wind up no different from the Berserker. I ain't lookin' to become a war machine for real." ― Yu Ominae[source]

Yu Ominae Sleeping Gold Rush

A slacker at heart

To most of his friends and fellow classmates, Yu is known to be an outgoing, optimistic, and cocky individual whose kind-hearted traits made him quite popular in his school. Although he may be often regarded as lazy and vexatious, particularly when he is usually seen falling asleep during class sessions by his teachers and may cause mischief with certain people like the Sasahara sisters, he still demonstrates the willingness of living his normal, school life to the fullest by attempting to maintain his adequate attendance record and grades. The major factor that proves this desirable task to be a challenge is, unbeknownst to most of his acquaintances, him being frequently called upon by ARCAM to conduct black-ops as a Spriggan operative.

Yu is dedicated in assisting ARCAM with sealing away dangerous, ancient technologies from falling into the wrong hands. He is loyal to those who he believes is fighting for the greater cause, but has no problem turning against them if he discovers that they are corrupted, as evident by him admitting towards Iwao Akatsuki that he will cause the destruction of ARCAM with his own two hands if they were to go against their philosophy and collect artifacts for non-benevolent purposes.

Yu Ominae not just a war machine

Yu reflecting on his connection to his daily school life and how he refuses to simply identify himself as a war machine.

Yu's dark history involving him being one of the test subjects for the COSMOS project conducted by the U.S. army has dramatically affected his childhood life. Even after safely returning back home with his adoptive sister from the supposed COSMOS fiasco, Yu was mostly stuck in his murder machine state where he will ruthlessly kill anybody who pose a significant threat to him and his loved ones without remorse. Despite later on managing to mitigate this mental state thanks to the help of his uncle and Oboro, he still occasionally reminds himself of how much he loathes of being simply a killing machine, and thrives towards being better than what he was in his past. This is showcased several times such as him attempting to convince Jean Jacquemonde against finishing off the injured Little Boy with his SPAS-12 at Mt. Ararat, Turkey, or knocking out Trident soldiers with his fists during his mission in Romania, much to Jean's annoyance in him being reluctant in just shooting them with firearms to silence them swiftly and permanently. Yu, however, has and will still kill per his duty as a Spriggan.

Yu can be occasionally reckless and stubborn, particularly until his final fight with Oboro, he can be too reliant on his A.M. suit and vastly overestimating the power of it (which its effectiveness decreases as the manga progresses), despite Oboro advising him in ditching the suit several times. He also underestimated Colonel McDougal's child appearance, causing him to not predict his psychic attacks when he refused his offer to surrender. Since the A.M. suit cannot greatly withstand the attack, Yu suffered excruciating pain and was nearly killed, as the result. His stubbornness can come into a positive light, however, as he is often shown to not concede easily when the odds are significantly stacked against him.


Early Life[]

Yu Ominae seeing corpses parents

The young Yu witnessing the corpses of his biological parents.

Yu was born in Japan and is an only child to his unknown parents. Not much birth information is given about him. When he was five years old, he and his parents were part of the ARCAM excavation team in Iran. At one point, however, the U.S. army assaulted the site, killing everyone involved there including his parents. Yu was not present in the site during the attack and managed to avoid death. Unfortunately for him, he would later walked to the site alone, only to discovered the corpses of his parents.

Yu Ominae founded by Oboro

Yu, in the state of absentmindedness, is discovered by Oboro after murdering his fellow COSMOS officers.

Yu was later placed in an orphanage where he would eventually get acquainted with Rie Yamabishi. He was then taken in to the United States by his uncle, Takashi Ominae, and his adoptive sister, Akiha Ominae. However, Yu was randomly abducted and was subjected to the U.S.'s top secret military project, Project COSMOS, where him and his fellow COSMOS children were brainwashed, experimented on, and received special forces-level training to be transformed into ruthless killing machines. He was assigned a codename, "Number 43", and partook in an operation involving a raid on an archaeological site somewhere in South America along with other COSMOS commandos. Yu and his unit wiped out all presences of security guards and civilians there. When a couple attempted to escape from the unexpected massacre, Yu confronted them and held them at gunpoint with his H&K MP5SD, and they were swiftly executed. Their lifeless body posture then reminded him about the deaths of his parents, sending the vengeful Yu into a rampage of killing almost all COSMOS officers and soldiers within the site. Afterwards, Oboro just happened to come across the aftermath of the massacre and found a bewildered Yu inside a trailer. Yu attempted to kill him, but Oboro managed to incapacitate him. He would then escorted Yu back to the ARCAM Corporation.

Yu was eventually reunited with his uncle and sister, but his mental state failed to be improved from the incident. At one point, a group of three robbers barged into Yu's house and attacked Akiha. They also attacked him when he entered the room where she was taken hostage, and one of the robbers held him at knife point. Yu did not hesitate to relive himself as a COSMOS commando and quickly killed two of them. When he was about to kill the last one, Akiha intervened and injured her left shoulder from Yu's knife swing. The surviving robber bolted out of the house due to intense fear from what he just witnessed, and Takashi investigated the scene for him to see two dead robbers, an injured Akiha, and a screaming Yu. He slammed Yu against the wall and told him that there is more to life than just being a murder machine. Takashi persuasion skills have helped Yu in regaining his humanity. He then traveled around the world with his uncle for a while, but eventually signed up to become a Spriggan field agent for ARCAM and underwent training with Oboro and his knife instructor, Bowman.

First Mission[]

Yu Ominae sees Megiddo Flame

Yu witnessing the activation of the Megiddo Flame.

For his first assignment as a Spriggan operative, Yu was tasked in infiltrating the M.A.T. Research Lab in Tokyo and preventing the U.S. military from misusing the Megiddo Flame that can potentially cause the destruction of the entire city if activated. Director Yamamoto provided him a newly issued A.M. suit during their briefing that is designed by Dr. Mayzel, in which it delivers significant protection to Yu from bullets and melee attacks. The given task only serves as a mission directed to Yu, as he must also act as a demonstration to ARCAM that they are forces not to be easily reckoned with.

By the time Yu was deployed onto the facility, the Megiddo Flame's startup was already initiated by an American Machiner's Platoon operative, Mayor Hummingbat. This forced Yu to ditch the covert infiltration plans and speed things up. At one point, he came across a researcher there, who eventually revealed herself as Yoshino Somei. She gave him the details on what is really happening within the facility and urged him to put a stop to the impending disaster. He then came across Hummingbat in one of the hallways and the two commenced a duel. Yu initially struggled against Hummingbat's ultrasonic waves attack, but still managed to overcome it and neutralized him. With the help of Yoshino and Hummingbat being defeated, Yu ensured the Megiddo Flame crisis was placed to an end.

The Shrine of Fire[]

Eventually, ARCAM has invited professor Rie Yamabishi to Japan for the purpose of utilizing her talented translation skill to decipher their research. Yu was sent in to the airport as her escort. Unfortunately, when he arrived there, he witnessed Rie being escorted by two C.I.A. agents instead. He intercepted them and rescued her from being possibly kidnapped. He drove her back to the ARCAM building where Yamamoto is located. There, She mentioned to Yamamoto about in exchange for her performing the research for them, ARCAM would also fulfilled her special request by finding her long-time friend, Yu Ominae. Yamamoto questioned Yu about his confidence in not revealing his true identity to her as of yet, to which the latter responded with that he would prefer for her to not know about him partaking in a dangerous job. Some time later, he infiltrated Rie's hotel room and waited for her to come out the bathroom from her shower, although she initially didn't take kindly in him unexpectedly showing up in front of her. He asked her of her affinity with this "Yu Ominae" person, to which she explained her backstory about how she was placed in an orphanage after losing her parents in Japan, and she was unable to successfully socialize with other orphans, resulting in her to feel lonely and depressed most of the time. She mentioned that all of that has changed the moment Yu Ominae approached her to be her trustworthy friend, and she desired to come back to Japan to see how far he has grown. Yu reassured her that he will help her in finding her lost friend after she managed to finish her work, and that he will do his best to accompany her in the meantime.

Ominae revealing A.M

Yu showcasing the invading U.S. army soldiers his A.M. suit.

The next day, Rie was fully briefed by Yamamoto about a shrine located by ARCAM explorers deep within the unexplored forests of Mount Fuji. They eventually discovered that the walls of the ruins was covered in an unexplored Jindai script, requiring Rie to decrypt it. When Rie attempted to use the elevator to access the fifth floor where the computer is located for her work, she is suddenly greeted with a tall U.S. army soldier standing in front of her as soon as the doors are opened. She tried to evade them until Yu arrived shortly and neutralized them swiftly. After forcing him and the American soldier outside, he is shortly greeted by more soldiers waiting outside for him. He used this opportunity to introduced them to his secret, cutting-edge weapon, which is the ARCAM's own A.M. suit. With the suit, Yu is able to dispatched the soldiers without a hitch. As the couple remaining soldiers began to surrender, he becomes shocked by them being suddenly exploded by an unknown force. This is shortly later revealed to be the work of the Japanese KGB agent, Koichi Moroha. He attempted to kill Yu with his sacred art of the Moroha clan that is called the "Tornado Blast", although the latter would negated this attack with his suit's psychic waves power. Koichi escaped from him for now, notifying him that he will capture Rie for his own benefits.

Later, Yu was onboard with Rie in an helicopter towards her request in investigating the shrine physically for herself. However, he eventually spotted an unidentified missile rapidly approaching the aerial vehicle, forcing him to react quickly by falling out of the helicopter with her on his hands. He used the helicopter rope for them to to barely survive the landing. Rie was starting to panic with the amount of stress she is receiving from all the dangers that is currently occurring and wonders why not give the ancient civilization's legacy to opposing forces if they desired it immensely, to which Yu replied with that they cannot risk having them fall to the wrong hands. He gave her the ancient plate that is written in ancient Hebrew, describing their request for future generations to protect their technologies from those who planned to use them for non-benevolent purposes. He then has her following him within the forest until he created a hole for her to hide in while he dealt with the Spetsnaz troops ambushing them. Eventually, he came across Viktor Stolov, leader of the Spetsnaz unit conducting the operation of capturing Rie. Viktor is proven to be a formidable opponent with his numerous brain augmentations and an altered DNA providing him massive advantages in the battle against Yu. After some struggles, Yu managed to neutralize Viktor by slamming his head on the ground. He then ran back to the hole where Rie was hiding, only to discover dead Spetsnaz soldiers near it and her absence. He suspected Koichi has something to do with the massacre and Rie's disappearance. Therefore, he dashed to the location of the shrine, but then eventually discovers that Mount Fuji has erupted, deducing that Koichi must be the one to activate it.

Ominae struggles against Moroha

Yu struggling against Koichi Moroha's attacks.

Yu then saw the legendary eight-tailed fire serpent emerging from the volcano. He noticed Koichi and Rie near the shrine, with the latter being held captive by the former. Before Yu could react, Koichi used a sphere-like object to direct the massive flames towards Rie, seemingly turning her to ashes. Filled with rage, Yu battled out against Koichi, although he initially struggle against Koichi's Hihirokane blade made out of Orichalcum, the same material used for Yu's A.M. suit, and his ability of controlling the flames. Yu is eventually overwhelmed by Koichi's powers. Then, Viktor unexpectedly show3e up and attempted to murder Koichi for his betrayal to the unit, but is eventually killed by him. Yu used this time to recover and approach behind him. Koichi tries to use his blade to execute the Spriggan, although Yu blocked the attack with the ancient plate, breaking Koichi's blade in the process. Yu punched Koichi in the face and threw him to the scorching flames, killing him in the process. He then picked up the sphere object from the ground and approached the shrine to place it back where it originates from, only to find Rie being still alive. He also noticed that Rie has discovered his true identity while being captured by Koichi. After putting a stop to the eruption, both Yu and Rie escaped from the forest. Yu would then received a handwritten note from Rie after her departure from Japan to the U.S., telling him that she is glad to meet him again and to take good care of himself.

Legend of the Mask[]

After a brief mischief with his school teacher and the Sasahara sisters, Yu drove to the ARCAM Research Center on his YAMAHA V-max motorcycle where he expressed his frustration to Yamamoto about Yu having barely enough time to focus on his studies due to him getting constantly harassed with missions to undertake. Yamamoto apologized for the inconveniences, but told Yu that something urgent has popped up. He revealed him the photo of the Mask of Palenque, an artifact that was stolen from a Mexican anthropological museum back in December of 1985. Yu then shortly afterwards noticed the Sasahara sisters' father, Kouichi Sasahara, being presented in the photo, in which Yamamoto explained that he could be the one with the possession of the mask, along with the ten rings. He assigned Yu in infiltrating Kouichi's place and retrieve the possessions, much to the latter's dismay of acting like a thief, especially when doing on his friend's house. Yu then finally accepted the assignment after Yamamoto warned him that those who have the mask in their possession all died under mysterious circumstances, and determines that the Sasahara sisters' family could be in danger as well.

Ominae confronting Kagaho

Yu confronting Kagaho, who appears to be under the influence of the mask, at the front of her house.

Later, Yu arrived at Kouichi's house to initiate his infiltration mission. Unfortunately, he is eventually discovered by Hatsuho Sasahara, who initially presumed he was attempting to commit a burglary within her family's house. Suddenly, a loud noise of shattered glass is heard from the house, prompting Yu to investigate there immediately. There, he and Hatsuho founded the latter's father to be severely injured. When trying to go outside to get help, Yu saw a group of werejaguars and a masked figure, who he assumed to be Kagaho Sasahara, appearing at the front. She attacked the jaguars and Yu when attempting to escape. The jaguars then turned to attack Yu and Hatsuho, in which he is about to defend himself and her when an elderly sorcerer suddenly showed up at the roof, explaining that he will be the one who will deal with the mask. Yu is not pleased with his presence and attempted to fight him, but discovered the sorcerer's appearance is just an illusion, and he warned Yu to not be involved in this situation. With Kagaho on the loose, Yu made it his priority to save her from further destruction.

Yu is later seen at the hospital where Hatsuho's father is recovering from his injuries. After some talk with Yamamoto, he requested Yu to save her daughter. Yu and Hatsuho then headed to the rooftop where the latter expressed her concern about her twin sister's well-being and how difficult it would be to track her down. Yu reassured her that Kagaho will come by to them eventually by him obtaining one of her ring's earlier. Kagaho arrived shortly to them and demands the ring to be given back to her, to which Yu refused unless the mask figure could remove Kagaho from its influence. In addition, the sorcerer and werejaguars began to appear as well. Yu dueled against Kagaho and was nearly victorious at several points, but the rings that Kagaho possessed provided her with immense power. Yu and Hatsuho, eventually, nearly fell off from the roof, only for Kagaho to levitated both of them and saved their lives. Kagaho escaped again, with the sorcerer eventually being a center of attention for Yu. As he attempts to neutralized him, the old man fell off from the roof, seemingly committing suicide in the process.

Ominae vs Metrisk

Yu battling out against a Machiner's Platoon deserter, Dutch "Iron Arm" Metrisk.

Back at the ARCAM Research Center, Yamamoto reveals the sorcerer identity to be that of Sanchez, a fortune-teller who believed to be the direct descendant of Tezcatlipoca. Yu then notified Yamamoto that he will be leaving from Japan to Mexico soon as he believed it is his next lead for Kagaho. He reluctantly bought Hatsuho with him after her incessant requests in going with him to see her sister. After arriving in Mexico, Yu and Hatsuho went to one of the plane's storage warehouses where Kagaho is likely to be hiding within the plane. Eventually, Kagaho appeared from the plane's side door, to which Yu formed contact with and attempted to convince the masked figure to remove its influence to Kagaho. Unfortunately, the discussion came to a sudden halt when the door is suddenly blown up by someone. The man is revealed to be Major Dutch "Iron Arm" Metrisk, a war machine sent as a hitman to eliminate Yu. The two commenced a duel, with the battle resulting in Dutch blowing up the warehouse with a grenade, and Yu barely escaping from the blast.

Yu and Hatsuho then decided to stay in at a hotel for the night to rest. After a brief conversation with her about Kagaho's feelings to him, he fell asleep. He then woke up afterwards by a distress voice of Hatsuho and discovered that she suddenly went missing. This prompted him to drive in the jeep on a raining night while desperately searching for her. At one point, the same adversary that Yu fought back at the Mexican airport has suddenly ambushed him at the top of the jeep. Yu successfully have Dutch fell off from the vehicle and held him at gunpoint with his handgun. Shortly afterwards, Hatsuho, being held captive by the werejaguars, and her father that is currently under influence by Tezcatlipoca, appeared from a cliff behind him. He demands Yu to surrender and has Dutch finish him off in exchange for Hatsuho being able to live further. Hatsuho then formed a risky maneuver in order to save Yu by attempting to run away from the jaguars, although one of them eventually seemingly fatally swiped her from the back. As he watched her helplessly falling from the hill to the river, Yu dashed in the water to save her from drowning. Unfortunately, Yu lost track of her the moment they fell from the waterfall. He blamed himself up for failing to save her and is eventually held hostage by the jaguars. Dutch would then came out of nowhere to not only rescue him, but to have Hatsuho in his arms as well. He told Yu to back off for now as he deals with Tezcatlipoca, although he also warns him that the next time they meet, he will attempt to kill the Spriggan.

Ominae fighting against Werejaguars

Yu firing his rifle against the werejaguars.

Yu escorted Hatsuho back to the jeep and scolded her for her earlier impulsive stunt. He then armed Hatsuho with an SMG, and both drove around in a search for Kagaho's whereabouts. They eventually got a lead on her location and saw her surrounded by werejaguars. They assisted her by opening fire on them, and one of the jaguars eventually swiped the mask off of Kagaho, finally removing its influence on her. Dutch then suddenly appeared to mow down the additional remaining jaguars with his LMG weapon for him to have a fair fight against Yu. Yu defeated him, but later discovered his body went suddenly missing shortly after falling off from a cliff. He then witnessed Dutch to be transformed into a werejaguar by the work of Tezcatlipoca. He further battled against Yu, but eventually died by him stabbing him in the torso. Yu is infuriated by Tezcatlipoca's sadistic work and vowed to tear him apart.

Yu, along with Kagaho and Hatsuho, continued driving in the jeep to track down Tezcatlipoca. Along the way, Yu has already requested a package from the ARCAM's Archeological Research Lab as a tool in neutralizing Tezcatlipoca. They eventually encountered thousands of werejaguars that are waiting for them. Since escaping from them is not viable, Yu resorted to fending them off with the equipment he have, but the large werejaguar eventually impaled him with its claw. As the situation grew to be helpless, he heaard a voice from the masked figure, revealed to be Quetzalcoatl from earlier, mentioning that all of the werejaguars are just illusions and to not give in to fear. The illusions eventually faded away, and the group find themselves near the Uxmal pyramid that was initially referred to as Tezcatlipoca's fortress. Tezcatlipoca then exposed himself from the fortress and began to attack the group. Yu unboxed the package from ARCAM in the jeep to reveal the Mirror of Mara that is meant to trap figures like Tezcatlipoca. After a long and grueling battle, Yu successfully has Tezcatlipoca's spirit sealed in the mirror. Quetzalcoatl thanked Yu and the others for the assistance before transferred itself to its home planet. With that, Yu ensured that Tezcatlipoca is finally gone and the Sasahara sister's father finally recovered to his normal state.

Noah's Ark[]

Back at the ARCAM Research Center, Yu is briefed by Yamamoto about the recent discovery of Noah's Ark within Mount Ararat by the ARCAM Archaeological Research Team. The team also uncovered another message plate, describing that Noah's Ark must not be interfered under any circumstances, otherwise those who ignore the warning will be perished. Yamamoto also informed Yu about the recent attack at the ARCAM Mt. Ararat Research Site by unidentified intruders. Concerned about the vulnerability of Noah's Ark, Yamamoto tasked Yu in heading to Ararat to protect the Ark and the ARCAM staffs researching it.

Ominae Prepping for Battle Ararat

Yu, armed with new equipment provided to him by Dr. Mayzel and Margaret, preps for a battle ahead of him at Mt. Ararat.

At the research site, Yu is eventually contacted by Dr. Mayzel about the recent developed equipment that is researched by him and Margaret. He gave Yu a new combat knife made out of Orichalcum and armbands equipped with a wire anchor. Eventually, they overheard the alarm going off in the facility, with the announcer stated that the dig site is being invaded by intruders of unknown affiliations. Yu equipped the A.M. suit and his new gadgets before heading out to the battlefield.

The ARCAM security troops attempted to hold off the intruders, but they were eventually no match for Major Fatman and Little Boy's more advanced firepower and equipment. Yu arrived to the scene shortly after all of the ARCAM troops are dead, and after he vowed to avenge his team's deaths, he battled against the Machiner's Platoon duo operatives. Unfortunately, Yu is unable to neutralize them as he noticed they are also equipped with armor made out of Orichalcum, and Fatman eventually pinned him against a container. As all hope appeared to be lost for Yu, a rocket-propelled projectile came out of nowhere that striked Fatman on his back. The shot came from a French Spriggan agent, Jean Jacquemonde. He then assisted Yu by dealing with Little Boy for him, while the Japanese Spriggan dueled against Fatman. Yu eventually incapacitated Fatman after stabbing him in the torso, and Jean has Little Boy pinned to the ground. However, Jean is not amused with Yu sparring Fatman for the atrocity he just committed and shot him in the face with his shotgun without showing any remorse. As Jean aimed his shotgun next to Little Boy, Yu prevented him from doing so, saying that they are not in a murder business and there is no purpose in executing the surrendered enemies.

Ominae struck by McDougal

Yu being critically injured by Colonel McDougal's psychic attack.

Yu and Jean then traveled to the dig site where Noah's Ark has been uncovered. The former then checked in on Dr. Mayzel and Margaret in their research room where they analyzed the triangular plate that was discovered along with the existence of the Ark. Afterwards, Yu attempted to interrogate Little Boy in his prisoner cell, despite him refusing to answer any of the questions. He informed Yu that a "demon" will be arriving shortly to take over the facility. That "demon" revealed to be Colonel McDougal, who just breached into the facility along with the rest of the Machiner's Platoon soldiers. McDougal demanded Yu to hand over the triangular message plate for him to access to the Ark. Yu refused to abide to that order, and McDougal shortly injured him with his psychic attack, nearly killing Yu in the process. The helpless Yu then watched Mayzel and Margaret escorted McDougal to the Ark as he is now being held prisoner by the U.S. military. Luckily, Jean came in to the rescue to save Yu from capture. Little Boy noticed Jean's presence and shot him with his SMG. What followed next is Yu witnessing his friend's transformation into a lycanthrope and the massacre of the entire U.S. soldiers from him within the facility.

After Jean transformed back to his human form, The duo proceeded to head inside the Ark to rescue the ARCAM scientists from McDougal. Along the way, they find creatures from the ice ages that are already extinct within the Ark. They eventually traveled far enough to encounter McDougal and the scientists. McDougal then activated the Ark that caused an earthquake and a dramatic change of the Earth's weather. Yu had Jean escorted the scientists out of the Ark for him to engaged McDougal by himself. His psychic attacks had proven to be an incredible struggle for Yu to overcome against, but he eventually stabbed him in the torso with his combat knife. McDougal then activated the Ark into self-destruct mode after freeing himself from Yu's grasp. Yu attempted to escape, but eventually fell to unconsciousness from hemorrhage until Jean suddenly appeared to rescue him, and both escaped from the Ark. Afterwards, the victory of the destruction of Noah's Ark had the duo being cheered upon by the remaining ARCAM staffs.


Some time later, Yamamoto had received intel that the British archaeological group somehow managed to discovered another work from ancient civilizations that is often referred to as the "Berserker". He contacted Yu about this situation and had him meet up with later for further briefing. As Yu is exiting the school, a girl by the name of Okabe walked up behind him and requested that he will come to school this Friday. Kagaho appeared shortly and explained that Okabe wanted Yu to act as her final send-off to another school at the track-and-field meet. Yu promised to them that he will be there when he gets a chance.

Ominae holding S.A.S

Yu holding an S.A.S. commando at knife point.

Yu is already at the forest approaching one of the British facility by the time night time has occurred. As he is ambushed by the British's S.A.S. commandos, he attempted to contact his unit, Red Company, with his callsign of "Fairy" about their status, but to no avail. He assumed they were wiped out earlier by the S.A.S. and is now a lone-wolf of this operation. Regardless, he managed to take out most of the S.A.S. troops, minus one who he spared and let him escape. He then noticed the last surviving Red Company member who was mortally wounded and performed a mercy killing on him.

Yu eventually discovered the British facility where they kept the Berserker in their underground lab. As he approached the base, he suddenly discovered that the alarm had already went off, followed by an explosion from the place. This made him realized that the Berserker had already been activated, inciting him to abandoned his infiltration plan and headed inside the facility. There, he encountered a Lieutenant Colonel, Maria Clemente, who was injured by the attacks from the Berserker.

Ominae jumping in to the race

Yu jumping in to the race just on time.

They eventually retreated to the command center after Yu initially failed to destroy it. After convincing Maria to assist him in killing it, they formed a plan where Yu will have to lure it to the explosives testing facility so in the scenario where it blew it up, the explosion would not spread to the outside world. Unfortunately, Maria is locked out of the facility's controls and discovered that the civilian workers are trapped in a nuclear reactor room. While she investigated the cause of this, Yu went after the Berserker and instructed the workers to escape from the room. The Berserker then transferred its attention to Yu and began chasing after him. Maria then continued to update Yu on his current position and the facility's layouts. He eventually lured it to the shelter and shot the steam pipes to weaken its attacks. He then used this opportunity to behead it with his combat knife. Afterwards, he narrowly escaped from the Berserker's self-destruct system by entering into the maintenance shaft. He exfiltrated from the base and eventually barely made it on time for his school's 10th annual track-and-field meeting. He then managed to win the race for the Year Two's Class B.

The Forest of No Return[]

ARCAM later discovered a miracle drug by the name of "Soma" that is known to deliver immortality to those who possess it. It is said that the drug is at home within the so-called, "the Forest of No Return". Yu was briefed by Yamamoto about this, with the latter being concerned of ARCAM's method towards sending their operatives to an extremely dangerous location, in which those who were originally sent there are unable to report back successfully. In addition, Yamamoto found out that other organizations are attempting to obtain the relic for themselves, including the infamous weapons development organization, Trident. Regardless, he reluctantly tasked Yu in simply investigating the perimeter of the forest and report back to ARCAM. He emphasized Yu to avoid entering the forest under any circumstances.

Once arrived at the forest, Yu eventually witnessed an Indian cult worshipping the statue of Rama that appears on the main display. However, he also spotted Yoshino attempting to steal the statue for herself by snatching it upon utilizing a rope to quickly swooped in. Unfortunately for Yoshino, her rope suddenly broke and the cult did not take kindly of Yoshino's action, causing her and Yu to be chased from them. Both managed to escape from the cult, and Yu warned Yoshino of his task regarding him investigating the infamous, "the Forest of No Return", and suggested to her to leave while she still has a chance, much to her thrill-seeking aspect setting a preferred judgement on her decision of escorting with him throughout his mission.

Yu and Yoshino eventually discovered a hut that is alone within the forest, prompting them to investigate it. Before that, however, Trident troops came in suddenly in an attempt to ambushed them, but both investigators managed to neutralize them. Inside the hut consisted of a dead Trident unit killed by an unknown cause. As Yu began to search outside the hut, the hut became imploded with numerous, massive roots sticking out from it as Yoshino was barely able to escape from it. Both ran from an unknown force to a secured area, and they find a Trident soldier escaping from the danger as well, in which they decided to interrogate him for determining Trident's true intention behind their operation in the forest. However, they were interrupted by a vengeful spirit approaching behind Yoshino, killing the Trident soldier itself, and forcing Yu to use his psychic waves attack to fend off the spirit. Both then felt a sense of being watched by a figure, in which Yu decides to locate a place for setting up camp.

Ominae fight Akatsuki

Yu in combat against Iwao.

Sometime later, the figure continued to stalk Yu and Yoshino during their rest at the camp. After being prompted by Yu to expose itself, it eventually identified himself as Iwao Akatsuki, the leader of Trident's mobile unit. The latter proposed to the former of forming a temporary alliance towards discovering an exit from the forest. Yu declined, however, stating he is unable to trust Iwao. He then challenged Yu to a duel, but their fight was eventually interrupted by Yoshino opening fire on them by her FAMAS rifle. Iwao withdrew from the fight, and informed Yu that they will finish the fight next time.

Twenty hours later, Yu and Yoshino continued to search around the forest for an escape route. At some point, they came across corpses and were eventually ambushed by the forest's ghouls, consisting of undead ARCAM and Trident unit. Iwao arrived unexpectedly and assisted both of them in fending off the possessed spirits. When Yu called out Iwao of possessing an A.M. suit similar to the design of the former, he explained that part of the development of Trident's very own prototype Orichalcum suit was from data analyzed from ARCAM's former conflicts with the Machiner's Platoon, much to Yu's disgust of discovering Trident's will towards taking lives for their weapons development. Yoshino eventually pleaded him to have Iwao as a temporary ally to increase their chances of escaping from the forest alive, in which Yu reluctantly agreed upon.

Eventually, the group came across a Buddhist shrine by Yoshino's sense of a devastated spirit, in which she proceeded to initiate her spirit channeling for communicating with the dead. Upon the spirit questioning about who disturbed its slumber, Yu requested it to share info surrounding the setting of the forest. The spirit informed Yu about those who entered the forest can never exit from it, but still delivered some insights of the forest's history where a legend figure, "The Great Hero Rama", fell into a great despair upon the discovery of his love interest, Sita, by the evil King Ravana. The forest fell into a curse by Rama's curses of desperation. The group is then informed about an ancient text containing a method of creating the nectar of immortality, Soma, in which it was decided to be sealed within the forest by the same spirit who was a priest man before his death. He then recommends the group to save themselves the trouble and succumb to the forest's deadly effect. Yu, however, did not take kindly from the words of the spirit and demanded the location of the forest's core. He then told him the location of the "Cursed Tree" that is mentioned to be the largest of all within the forest, and destroying it would release all of the spirits. With the vital information gathered, Yu and his fellow two teammates set out for the core.

After battling their way through the hostile spirits, Yu and Yoshino eventually came across the cursed tree. The former attempted to damage it by throwing an explosive ordinance, but got knocked back from the tree's ricoheting the explosion waves towards him. They were then nearly surrounded and consumed by the overwhelming vengeful spirit forces, but luckily, the statue of Rama fell from Yoshino's backpack, causing the spirits to drift away from it. Yu then grabbed the statue from her and made his way to the center of the cursed tree, in which combined with his super psycho blow, caused an explosion that drifted the remaining spirits away and finally breaking the forest's eternal curse. The aftermath of the battle had Yu exhausted, in which Yoshino used this distraction as an opportunity in snatching the secret text of Soma from the tree, although he eventually discovered her intentions and demanded to hand it over towards him. Iwao appeared shortly afterwards with the request of obtaining the secret text from them. Yu declined the offer with the reason of not allowing to create any additional conflicts, but Iwao questioned Yu of his loyalty towards ARCAM's philosophy with the possibility of the organization suddenly abandoning it for malevolent purposes. Yu responded, in that case, he wiil attempt in destroying ARCAM himself. Baffled by his response, Iwao eventually withdrew from the site with the promise that they still gonna settle the score with each other. Yu and Yoshino then successfully escaped from the forest.

Ominae Motorcycle

Yu arrives to Yoshino's private school with his motorcycle attire.

Some time later, Yu arrived at Yoshino's private girls school on a motorcycle with the intent of sharing with her a vital information regarding the origin of Soma: essentially, it's main ingredient from the plant, Ambrosia, went completely extinct due to the climate change, meaning it's no longer possible to manufacture Soma. He then informed her that the picture she took of the ancient text will not be worth of an investigation. Before Yoshino could fully processed the unexpected news she just received, Yu immediately drifted away from her on his vehicle.

The Crystal Skull[]

Back at the ARCAM building, Yu was reading a newspaper of an incident involving the brutal death of the Tokyo university professor of archaeology, Kawahara Shozo, in the streets of Alexandria, Egypt. Yamamoto filled in the details regarding his contribtuions to ARCAM's archaeological efforts and his body discovered in pieces. A crystal skull that the professor was carrying before his death has been stolen as well. Yamamoto then instructed Yu to travel to Egypt for the purpose of securing the skull before it falls to the wrong hands.

Upon reaching the country, Yu eventually made contact with one of professor Kawahara's relatives, Suzuko Kawahara. The two initially struggled in forming a bond with each other as Suzuko blamed ARCAM for changing his father's priorities away from the family and was unable to take Yu seriously based on his high-school like demeanor and appearance. Shortly afterwards, they were suddenly ambushed by Neo-Nazis men. Yu safely escorted Suzuko out from danger and neutralized the men himself. Later at the hotel, Yu called Yamamoto to analyze about German businesses that were currently operating in Alexandria and Cairo. Suzuko then disrupted their conversations by demanding information of the current situation. Yu then showed her the photo that depicted the authentic crystal skull made from a unique material, instead of the ones shown at the British museum that were fake replicas. The real one was sought after by numerous organizations after an information was leaked towards its capability in forming nuclear fusion as it can produce two hundred million joules of energy. Yu then requested Suzuko to go back to Japan and allow him to complete his mission. The latter refused, however, stating that she must grab hold of the skull herself as otherwise, she will live the rest of her life in regret from unknowingly determining the kind of stakes her father formed with him siding with ARCAM over his family.

Yu dueling against Bo Brantz

Yu battling against Bo Brantz.

The two then drove around the town until they came across a building that is likely home to the Nazi co-conspirators. Yu then barged into the building where the Nazis associates are currently operating their businesses. One of the members, Bo Brantz, challenged Yu in a duel. Yu was nearly victorious against Bo, but was suddenly ambushed and temporarily neutralized by "Mirage" from his ubiquitous force of Qi. He narrowly then escaped from his enemies and retreated back to the hotel room where Suzuko aided in easing his injuries. Suddenly, he received an anonymous tip from the telephone that provided the information regarding the Neo-Nazis activity of transporting the crystal skull somewhere in a trailer at 6 P.M.

Out somewhere in the desert, the Neo-Nazis were conducting an experiment show to showcase the power of the real crystal skull they possessed. Yu and Suzuko already formed a vantage point that overlooks the event. They eventually witnessed the explosion from a far distance that was created after the oscillation phase from the skull. Yu then managed to infiltrate at a theater in a later time where Captain Kutheimer showcased the event to his fellow Neo-Nazi men. Upon being discovered by them, he held a gunpoint at one of Kutheimer bosses and demands to deliver over the skull in favor of sparing his life. Unfortunately, the situation becomes further complicated as Suzuko was somehow held at knifepoint by Hans Schneider. Yu was forced to stand down and was held back by the Neo-Nazis during his attempt to rescue Suzuko. Oboro intervened, however, and neutralized Hans while taking down the rest of the army alongside Yu. He intercepted the fleeing Hans and broke his right arm before throwing him off the building from the window.

Yu then quickly rendezvous with Suzuko at the jeep in which they gave chase to the fleeing Neo-Nazis containing the crystal skull in their truck. They were desperate to the point where they attempted in sending arrays of bullets towards the duo during the middle of the busy town, causing civilian casualties in the process. This greatly angered Yu and vowed to ensured they do not escape from their horrid actions. Upon chasing them to the desert, he and Suzuko noticed a strange light emitting from the back of the Nazi's truck, suggesting they are planning to use the skull's power as a method of destroying the duo. Yu then quickly utilized his A.M. suit to throw a grenade towards the back of the truck, eventually dismantling the vehicle's and the Neo-Nazis operation. Afterwards, he offered Suzuko a firearm as a method of carrying out her revenge, in which the latter refused to do so as the skull was finally in her possession. "Mirage", revealed to be Oboro, met up with the two where Yu temporarily expressed his disapproval of receiving a strong blow from him. Oboro handed him the book containing the Neo-Nazis organizational details and is shocked to find an image depicting six dolls dressed as Adolf Hitler.

Spriggan (1998)[]

One day, Yu was dreaming about where he is partaking in a dangerous operation somewhere around the woodlands with all of unit, "Red Company", being already killed by the British commandos. He was eventually awaken by the sight of the British commando already aiming at his position, and noticed himself in a classroom setting with his teacher being visibly annoyed by his distracted behavior. After his teacher just announced that the class session has ended, Yu eventually noticed his friend, Tanaka, displaying a noticeable distressed facial expression at him. This incited him to investigate on his well-being at his school's rooftop. Upon Yu trying to assist him, Tanaka opens his gakuran coat with explosive charges attached to his hips. Yu attempted to assist him, but Tanaka eventually self-activates the detonator, creating an explosion that killed him and injured Yu.

Later at the ARCAM building during the evening night, Yu was printing out the photos from the printer, depicting the dead Tanaka during the aftermath of the explosion. Yamamoto entered the office, and the frustrated Yu demanded him an explanation about the meaning of the photos. Yamamoto then explained to Yu about the disappearance of the ARCAM excavation team from six months ago at Mount Ararat, and that an ARCAM Research Unit was attacked by the U.S. Machine Corps unit three weeks ago. Yu was frustrated about not being informed about those news, but Yamamoto stated to Yu that it was a trap to lure Yu into them. Regardless, Yu responded that he wants to overcome this with his own hands immediately and left Yamamoto's office.


Yu and Yamamoto are teammates at the first appearance. As Yu's supervisor, he has a duty to find out various OOParts that research team found at chosen region.

Yu and Rie are childhood friends.

Although teamed up as well-known partner, Yu and Jean considered as rivals.

Her first appearance that involved him made himself annoyed by her actions. Yu called Yoshino herself as low ranked artifact thief.

As his mentor, Oboro also tests his developing skills against Yu after fought against Jean. Unfortunately Oboro defeated by him by single punch. He also realized that Oboro did less training after defeated.

Yu meets his adoptive father and uncle somewhere in the Native American forest where Jean easily trapped by his hand-made trap.

His relationship with his adoptive sister and cousin also shown when she announces Henry Garnum.

Despite Yu and Precup being teammates, he was disgusted when Yu called him "gramps."


  • The name Yu means "excellence, superiority, gentleness" (優).
  • Yu's surname Ominae means "god seedlings" (御神苗).


Spriggan (1998)[]


  1. Spriggan Lunar Verse (From Software) - Official Guide Book (Shogakukan) - Background, page 138 - ISBN 4-09-102687-7 (Japanese)