Master Aux is a Keyblade wielder and active protagonist in Kingdom Hearts SOS. A former Antagonist, he is the strong, taciturn type until he spots something that causes him to grow livid.
Auxilius grew up in Iridescent Falls where he lived a very happy and peaceful life with his loving parents. This all changed, when his grandfather Kurt; whom he'd never met, arrived. Claiming to reconnect with his family, he told Aux stories of other worlds and keyblades. It wasn't long after that Aux found his world's keyhole and learned he could weild the keyblade; a trit his grandfather planned to abuse. After convincing his parents to let him train with him, he set off at the age of fifteen.
Kurt took him to a world called "Central Haven," where he took the role of the world's record keeper, and trained Aux mercilessly in secret. Aux grew stronger and his kind heart began to fade. At seventeen, he discovered Kurt conspiring against the leaders of Central Haven and planned to reveal his plans to the higher order. Before he could, Kurt used the help of a witch named Mizrabel to erase all his memories so he would no longer interfere or meddle in his affairs.
When he awoke, Kurt was said to have perished, and Aux was left alone, without memories or friends. It was then, he met a boy named Hikaru, who was kind to him and befriended him. A year later he met Kaida and the three of them became good, close friends. With Hikaru as his morale compass, and Kaida as his rival, Aux began to feel like his old self again. This friendship sadly did not last long.
Hikaru fell ill during Kaida's second mark of mastery attempt. Unbeknown to him, Hikaru's body was failing as a result of being the younger replica of his believed-to-be-dead grandfather. As Aux sat by his unconscious friend's side, he was deviously convinced by Nequa to implant a remnant of darkness in his heart to save his friend. When asked how it was possible, she explained that he had to remove the light in his heart and give it to Hikaru. Then and only then would the remnant keep Aux's heart intact so he could save his friend. Desperate, Aux took her offer and told no one. While Hikaru gained a keyblade, Aux's heart grew cold and distant. The remnant, eating away at his love for his friends. The months that followed showed Aux turn into an emotionless man who would align himself with powerful and cruel allies to further his own goals. Meeting No Heart, he left his home and friends behind to take part in his new master's enigmatic plan.
Part 1 (Dark Antagonist)
Aux, along with Nequa and Vanitas are the masked assailants who kidnapped Terra, Ventus, and Aqua from the Land of Departure. For unknown reasons, they were instructed to leave Master Eraqus behind and only abduct the students.
Aux first appears in Deep Jungle once the gang of protagonists have to split up in order to fulfill their objectives. He is seen talking with Clayton who seemed to be fairly annoyed with the lack of progress the masked people had been doing with their part of the bargain. Aux then agreed with Clayton, that he had been patient enough to be compensated, and proceeded to summon another Chameleon type heartless. After Clayton asked about the ship he was promised, Aux corrects him in saying that he was promised power and a vessel. He then reveals to Clayton that he is the vessel for the power, which was the heartless that was just summoned. The chameleon then proceeded to pounce on Clayton.
Aux is later seen alongside Vanitas and Nequa in a faraway location. Aux is told by Vanitas that his former friend was there to most likely convert Aux back to the side of good. Claiming he had severed past ties, Aux remained at Deep Jungle as the other two left, lamenting that Hikaru had come.
Aux appears in the Great Forest watching the origins of Bambi take place. With his appearance, all the animals fled and Aux pointed his keyblade at the heroes, questioning why he did not yet leave. Realizing that the SOS wielders was an outsider he decided that he had to take care of him. Not before revealing that the entire world was so close to the light, and how the pure hearts would make great heartless. Summoning some heartless for the party to deal with, Aux stepped away in a corridor of darkness.
Aux later returns holding Bambi at keyblade point, questioning why Bambi refuses the darkness. He claims that the other fawn; Ronno had accepted it, only to be interrupted by the protagonist crew arriving. He then proceeded to tell everyone that he had given darkness to another fawn, named Ronno, and called Ronno forth. Aux then decided to observe Ronno's developments, and watched as a battle ensued between the protagonists and the fawn. After the fight had ended, Aux seemed to think that in the end, Ronno was too young to fully utilize the darkness and came to the conclusion that without despair the heart could never fully accept it. Using his time belt to travel to the future version of the world, unknowingly taking the rest of the party with him.
Aux reappears once more, once Bambi and co. reach Bambi's mother. He is there to inform them that Bambi's mother is now deceased, and to taunt Bambi to darkness. He reappeared after the next time skip seeing that the scenery had barely changed at all. He then heard the growl of a deer, only to find out that it belonged to Ronno. Aux informed Ronno that he had never planned on meeting up with him again, causing Ronno to fall to darkness. Aux was also curious if he could force Bambi to fill a similar hate that Ronno felt towards Bambi. Somewhere during the fight with Ronno, Aux had used a fire spell to set the forest ablaze. As Aux watched the forest burn, Bambi and company had reached him. He sensed no darkness within Bambi and wondered what more he had to take from Bambi before he would submit to the darkness. After hearing Bambi's answer, he deemed the results inconclusive. Summoning some heartless to fight them, Aux left through a dark corridor.
Aux appears towards the very end of the Dwarf Woodlands series of missions. Aux appears out of a massive corridor of darkness overlooking a small clearing. He was seen to be on his large motorcycle like keyglider with a large glass casket attached to it. After Nequa had appeared to join the duo of antagonists, Aux reappeared with the casket containing Snow White in hand. He then tells them that they have the Princess secured and that they can begin the abductions. When Krowley asks if Aux was actually helping them, he then refers back to the letter at Deep Jungle. When Vanitas starts to get angry with Aux, Aux simply denies any accusations and continues to stay silent. Aux then finishes readying the casket and gets ready to leave, only to be told by Vanitas that their discussion wasn't over, and Aux warning the party of protagonists to stop meddling.
Aux appears in this chapter towards the beginning riding on his keyglider at a walking pace alongside Nequa. The two are in some kind of dark abyss area with floating islands everywhere. He is also still tugging Snow White in her glass coffin using his keyglider. Aux first questions why their master had told them to simply depart before doing anything else, to which Nequa replies that she has no idea what goes on in his head. Aux then wonders about what Vanitas's mission is, but Nequa doesn't seem to have much of a clue about it either. Nequa eventually brings up the topic of their motivations for helping their master, to which Aux bluntly responds that he wants to study the heart. He continues to talk about how he is interested in finding out what makes a heart become corrupted, what makes them stay at bay from the darkness. He then tells how in order to do these studies he needs test subjects, which each mission allows him to further his research. When Nequa questions if he's one of those guys who just doesn't think hearts are just dark and light, Aux responds by saying precisely. When she tells him that things are about to get a whole lot darker, he responds again saying precisely.
Aux next appears in the room with Nequa waiting for Vanitas and their boss. When Vanitas comes through the corridor of darkness and admits that he failed in his mission, Aux questions what the mission even was to begin with. Vanitas refuses to tell him and instead starts to try and bring up how much distrust he has for Aux, to which Aux continually refuses the accusations being thrown at him. Once their master makes his first appearance, Aux remains silent only to confirm that they needed six more princess of heart. The master then sends Aux and Nequa together on the mission that Vanitas just failed, only for the master to tell Aux that out of all the three, he was the one who was trusted the most. He then reassured Aux that all of the things being hidden from him were not important to him, and as such he didn't need to worry about them. After being told to keep an eye out on Nequa, Aux simply responds by calling him master No Heart and leaves.
Aux appears in this chapter by coming out of corridor of darkness alongside Nequa carrying a battered and defeated Master Xehanort. Aux then throws Master Xehanort at No Heart's feet. The next thing Aux actually does this chapter is, going alongside Vanitas he takes Master Xehanort with him to the Cryo-chamber and asks Master Xehanort if he was concerned by the uncertainty of his fate, to which Xehanort simply replies that he wishes to see how this plays out.
Aux appears in this chapter by simply talking with Master Xehanort. He allowed Xehanort to be conscious above the neck so that the two may discuss matters of the heart. Aux, in surprise, responds to Xehanort by exclaiming that the heart is contained no matter what. It is then that Vanitas comes forth and asks Aux why Xehanort is currently awake. Prior to this, Aux had moved both Xehanort and Eraqus to a new location. When Vanitas asks Aux about where Nequa is, he states that he does not know. He then says that hopefully both her and the horseman attained what they were tasked for, simply because they were running behind on schedule as things were. Vanitas then jokes at Aux saying that they've got the time belt so they can go as slow as they please, only for Aux to tell him that that isn't how it works. He tells Vanitas that unless their opposition is within the same world, they have just as much of an advantage as the protagonists do. When Xehanort makes a remark towards Vanitas, Vanitas loses his temper once again and pulls out his keyblade only for Aux to counter by pulling out his own. Aux then tells Vanitas that prisoner or not, he will treat Xehanort with respect. Only when No Heart's voice boomed towards them did the two withdraw their weapons. After No Heart told the two that they could go all out if they wanted to now, he then tells Aux that he must seal Xehanort back up. When No Heart asks is this is a problem, Aux hesitates before saying that it won't be a problem.
While Aux doesn't directly appear in this world, he does appear in the form of Kaida's flashbacks. In the first flashback he is shown to be fighting Kaida and winning rather easily. While she still continued to fight him, he simply told her to know her limits or else she would die against him. Not being deterred by it though, Kaida continued to attack only for Aux to nearly end it, when someone (presumably Hikaru) shouted to stop.
He appeared again in another flashback. This time he was sparring with Hikaru, still beating him with ease. While Kaida continually made jokes about the two, she then told Aux that she had no idea what school he had learned his keyblade prowess from. It was here that Aux said that despite feeling as though he failed his old master, his next master he would pledge undying loyalty to. He then mentioned that he would continue to wear his mask until the day when he could remember who he was, for not wanting to look at what he believed "half" of himself. Kaida then gave him a little wooden charm in the shape of a lion, telling him that it was a lion due to male lions always being in the pursuit of getting stronger, to help find out who they really are. Furthermore, male lions always stubbornly protect what is theirs. After accepting the charm, Kaida then continued to tease the other two, only for Aux to comment that she was quite devious and whether or not her animal would be the fox.
Aux first appeared in Beasts' Castle after Belle and the Beast entered the ballroom, commenting about how easy it was to manipulate people's hearts. Luna then asked him what he had done with Snow White to which he just replied that she was in a far away place and now had more value on her. When Krowley tried to reach out to Aux, the latter began to tell his former friend that he was afraid of the darkness that had gained a hold of him. When Krowley tried to help Aux, he revealed that he just made the whole thing up and was just mocking him.
Aux then scoffed as the group referred to Hikaru as Krowley. He told him that he would benefit more from finding his own personal identity, rather than clinging onto someone else's. He then summoned a bunch of heartless, warning Krowley that the darkness was not meant for the weak-hearted. Before Aux left the scene, he gave a warning to Krowley, telling him that if he got in his way one more time it would be the end and revealed Krowley's true name to be Hikaru.
Aux then appeared later in the chapter as the group looked through the Beast's magic mirror to see Maurice. He was seen facing down Eclipse, who questioned why he was there, and that he had a lot to answer for. Aux responded that he was simply isolating his threats and waved away any other comments.
Aux then appeared once more at the end of the chapter. He was seen, having defeated Eclipse, and being very unamused by her chiding of him on the properties of darkness. When the Headless Horseman came into the picture, he asked him if he was followed, only for eight of the protagonists to appear as his answer. As Hikaru began to ask why he was doing all this, Aux explained that he had the ultimate goal of becoming darkness itself. When Hikaru continually tried to reason with him, which included throwing a whittled lion carvings towards him, the man simply charred the lion and told Hikaru that they were no long on the same path.
As Hikaru and the others began to get into a fighting stance, Hikaru told Aux that he was going to do him a solid and take him down. Aux responded by saying that he was going to do Hikaru a solid and keep him down. Aux then brutally and effortlessly defeated all the members of the party.
Hikaru then tried to stop Aux on his own, and asked him why he thought he would just let him leave. Aux, as he grabbed Hikaru's neck, then told him that there were three reasons. He stated that his ambition was out of his reach and that he only dragged people down. By this time, he had broken Hikaru's mask, and broke Hikaru's own wolf carving, only to state that the final reason was that Hikaru was too weak. After giving him one last warning to stay out of his way, Aux left the world.
Aux appeared part way through this chapter, in the usual dark hideout that the villains resided in. He was seen alongside Vanitas, waiting for No Heart and Nequa's appearance so that they may get the next steps to their plan. While Vanitas was complaining about how the Horseman wasn't working fast enough in getting the princesses, Aux asked him why he was complaining even after he was allowed to cut loose. After asking him what more his half heart desired, Vanits brought up the point that No Heart had told him to stop talking to Master Xehanort. Aux simply replied that Xehanort was more enjoyable to talk to due to giving him answers.
Vanitas then started to go on about how if Aux wanted to talk then he should go join up with the others from the Order. He continued to berate him about he couldn't sink further into the darkness due to both Hikaru and Kaida's existence, being the only lights that still exist within him. Aux stood silently during this time. He then spoke up once again when Nequa appeared with Mizu in tow, asking how she could possibly always be late. Aux then seemed to get aggrivated with Nequa as she had kidnapped a member of The Order. The last thing Aux had done during this segment of the chapter was ask No Heart where Yen Sid was, only to be told that he had been taken care of.
Road to Darkness Epilogue
Aux appeared at the end of the first part of the Epilogue to part one of Kingdom Hearts SOS. In it, his role was fairly simple as the last encounter of the Part. In here, he did nothing but taunt the wielders and relish the power of darkness that he was granted. When they fought him, he demonstrated their difference in strength by pummeling the group mercilessly and tossing them all into the darkness. While fighting his old friends, Kaida and Hikaru, he removed his mask to reveal his face to them, and defeated them with equal ease before saying a goodbye to them and having them tossed into oblivion as well.
Castle of Illusion Flashbacks
Game Central Station
Choosing to make the Mark of Mastery Exam more "interesting," Sho Minamimoto abducted Aux and implanted him during the 2nd part of the Exam. Replacing party members who had left, Sho chose to mask his apperance by giving him a Black coats to hide his face with the name "X" as a placeholder. Being partnered with AJ, they duo went to the Fix-it-Felix portion of the world. There, tthey were greeted by a small man, by the name of Felix, who seemed to be looking for someone else by the name of Ralph. When the group told Felix his villain was in another game, the short man started to panic, talking about how Ralph had gone Turbo (a term meant for people who went into a different game from their original one.) As the duo continued talking with Felix, they eventually a digital copy of Aden and Gwendolyn breaking a building, and sprung into action to stop them. The two managed to work together to take down the digital copies.
With the battle being done, the group then had to go with the contents of the game. With Ralph missing, the duo had to play the part of the villain, breaking the building while Felix fixed it. During this time, AJ and X talked about what they were taking the exam for, and during this conversation, X lowered his hood to reveal a face that looked identical to Hikaru's. While this shocking revelation took place, AJ could not ponder on X, now named Nigo's, identity, the two's attention was drawn to the Hero's Duty Terminal. Seeing some kind of great scuffle and problem going on from within, the trio of Nigo, AJ and Felix made their way into the game terminal.
As the groups returned to the main hub of Game Central Station, they recounted what had happened in their worlds and had various discussions with each other. It was soon that their current game master, now revealed as Sho Minamimoto, came and congratulated the groups on the efforts. However, as he continued to taunt the group, he then decided to give Nigo back his true form, revealing him to be Aux. Aux was incredibly confused, as was everyone else. Megumi then stepped in an announced that Aux would be joining them in their Mark of Mastery exam, much to the chagrin of everyone, though Aux seemed to have no recollection of anything he had done in the past year. While most everyone was feeling tense about their new amnesiac ally, the groups were eventually formed and the people went off to take the last part of their Mark of Mastery Exam.
Aux was partnered in a trio group with Hikaru and Kaida for the final phase of the Mark of Mastery. He took the form of a lion as he tried to understand why everyone was so uneasy and dismissive of him. The more the world continues, the further Aux seems to feel like his old self. He's blunt and awkward, but overall still trying to help Simba reclaim his Prideland throne.
As completed their exam, they were given the option to change clothes and head off to destiny island. Aux unlocks his dark aura again Before they leave, Hikaru gives everyone and SOS ring. He has a heart to heart with Kaida and Hikaru and the three mend their friendship, hugging it out.
Battle of 10,000 Heartless
As the gang had made it out of the city of Shibuya, they found themselves on the world of Destiny Island. Wondering where to go next, it was soon revealed that there victorious exit was not to be so simple. Instead, they were greeted by a man named Marshal Hughes. The man decided to attempt to prove himself once and for all by stopping the now Keyblade Masters. Summoning a horde of ten \thousand Heartless, Marshall seemed intent on stopping the group with everything he had. Shiro appeared to assist and the battle commenced.
Aislinn and Aux joining forces to fight the first one darkside, the giant dark creature proved no match for the duos onslaught of slashes. With the group's fate starting to look dire and the third wave of heartless on the horizon, the heartless seem to suddenly be intercepted by something. With a wave of newcomers joining the fray, the members of the Black Coats arrived along with Mizu and Oswald the Rabbit. Marshall summoned his Stormbringer Heartless, causing the group to split into teams to take it down.
With the group having defeated Marshall, they take a moment to lick their wounds and rest for the moment. Standing around, the group wondered what next to do, and thus began to walk alongside the shore of Destiny Islands. Seeing a set of boats on the shore, they decided to go and make their way towards them. However, their journey was not quite so simple, and they were stopped before making it to the boats.
No Heart has appeared on the beach of Destiny Islands, awaiting our heroes arrival. With their foe right before them, the gang all pull out their keyblades and attempt to do battle with No Heart. Destroying Aux's keyblade and revealing it to be the same dark one that he had as an apprentice, and covering the man back in his dark suit of armor, Aux and Kaida do battle. The battle itself is fairly one sided, as Kaida cannot match Aux and Aux cannot shake free from the control of No Heart. Plotting to use Aux to kill Kaida in front of all of their friends, Hikaru decides that he has to do something as well. Revealing that he and Aux are one and the same, and that he used Aux's light from him to keep living, Hikaru decides to give it back to Aux. Sacrificing himself, the boy turns into nothing more than a ball of light and merges with Aux, freeing the young man from his darkness.
Enraged by this development, No Heart walks over to Aux and Kaida himself to kill them. Knowing that they cannot actually fight No Heart, they instead do everything they can to stall his progress, and escape. With three separate boats to board, the group splits up and takes their boat to float down the sea.
Return to Central Haven
Aux can be shown as quiet, brash, and entrusting of others. He is very socially awkward in situations but is more the prepared to stand up for what he thinks is worth fighting for. He can take things very literally and did not catch on to humor quickly.
When attached with the Remnant, Aux was cold, but logical. He seeked only what was most useful and powerful. (Which is why he was so obsessed with unlocking the secrets of the human hear) His personality was very dark, but he is not without priorities. Unlike Nequa or Vanitas, he was very loyal to master No Heart and viewed the masked one as a mentor.
Aux is a very heavy and muscular build, mainly covered in Black and White armor. His belt, and under is comprised of steel toed shoes and black pants embedded with white chains along the belt and below the knees. His upper body however is more heavily armored. the reason for this is he greatly values his hearts and will protect it at all costs. His arms are covered with metallic and mechanical armor giving him great strength and defense. He wears a plated chest plate overlaying his cloth under armor. The helmet he wears is a pitch black iron mask with 4 fang-like spikes coming out of the top.
His casual attire consists of a black cap with a tribal lion design on it. He wears a dark grey shirt with a purple vest with a white trim overlapping. His pants are dark grey with a white design on the bottom. His wears black steel toed boots and brown fingerless gauntlets made from leather.
- Combo Lv1  (Equipped)
- Combo Lv2  (Equipped)
- Combo Lv3  (Equipped)
- Combo Lv4
-  Blend (Equipped)
-  EXP Writer IV (Equipped)
-  High Jump (Equipped)
-  Magic Lock-On (Equipped)
-  Cheer (Equipped)
-  Dodge Roll (Equipped)
-  Guard (Equipped)
-  Item Boost (Equipped)
-  Berserk (Equipped)
-  Damage Syphon (Equipped)
-  Lucky Lucky (Equipped)
-  MP Haste (Equipped)
-  Healing Guard (Equipped)
-  Cover (Equipped)
-  MP Rage (Equipped)
-  MP Gift (Equipped)
-  Critical Plus (Equipped)
-  Counterattack (Equipped)
-  Reload Boost (Equipped)
-  Second Chance
-  Second Wind
-  Auto Aura (Lv1) (Equipped)
-  Auto Aura (Lv2)
-  Auto Blot
-  Auto Data
-  Auto Master
|Fairy Godmother||Guardian Rush (3AP)||Reluctancy|
|Cheshire Cat||Guardian Wall (4AP)||April Showers|
|Strike Raid||Curaga||Bambi||Trip Around the Sun (5AP)||August Heat|
|Vorpal Blitz||Firaga||Baymax||Get'em!||Dec. Snow|
|Fist Bump||Graviga||Experiment 221||Trinity Limit (5AP)|
|Keyblades||Items||Accessories||Jobs (10 AP)||Auras|
|Starting Key||Potion||Musketeer Hat||Ranger||Darkest Fears|
|Jungle King||Ether||White Gloves||Summoner||Dark Impulse|
|Treasure Trove (I)||Balloon Letter||Moogle Badge||Paladin||????|
|Ferris Gear||Hi-Potion (x5)||Titan Chain||Dark Knight||Claymaker|
|Unbound +9||Phoenix Down||Energy Bangle||Black Mage||Firestorm|
|Frolic Flame||Item Ticket||Ray of Light||White Mage||????|
|Lady Luck||Job Ticket||Mystic Chain||Monk|
|Oathkeeper +4||Accessory Ticket||Red Mage|
|Circle of Life|
|Sweet Memories (M)|
- He enjoys the forest and waterfalls since they remind him of home
- Back in his homeworld, Aux had a talented knack when it came to repairing and building machinery.
- His father is a mechanic and his mother is an engineer
- Moogles make him very uncomfortable
- In flashbacks, it's shown that his grandfather; Kurt had mercilessly trained him to be a powerful keyblade wielder. As a result he is always vigilant and combat ready.