Who Is Allen Walker? 

Allen Walker (Japanese: アレン・ウォーカー Hepburn: Aren Wōkā), is the main protagonist of the fictional manga and anime series D.Gray-man, written by Japanese manga artist and author Katsura Hoshino. In the series, Allen is an Exorcist from the European Branch of the organization known as the Black Order. He uses an item called Innocence, which usually takes the form of a huge, evolving left arm to assist him in his battles.

Allen’s only known family is his adoptive father, Mana Walker, and adoptive uncle, Nea D. Campbell. During his training at the Black Order, he worked as an apprentice of Cross Marian as a part of the Marian Unit. He is usually accompanied by his golem, Timcanpy.


How old is Allen Walker

While his age was never exactly mentioned or described, he is generally determined to be around 15 years old from the start of the series. He was adopted by Mana Walker on December 25th, which became his birth date.. While his colleagues simply assume he ages normally like the rest of them, Nea, one of his enemies, noted that Allen might be growing younger during the time he possessed the young exorcist’s body. 


Allen Walker’s Appearance

Allen Walker appears as a male teenager of average height, revealed at about 168cm at the start of the series. Yu Kanda, another Exorcist from the European Branch, often teases Allen about his height although Allen has an average height and Kanda is simply a tall person. He also has a lean physique which has grown covered with scars over the course of the story. He has medium-length hair in the shade of light gray or white, which has grown to shoulder-length or at least a little longer. His eyebrows and eyelashes are of the same color. In the manga, he has silver/ grayish eyes in the manga and the anime aside from the Hallow anime, where his eyes are of a purple color. 

An easily identifiable mark on Allen Walker’s face is the huge scar starting from a pentagram at his left forehead running down in a line crossing his eyebrow and eyelid, right through his cheek and ends near his chin. An extra line of scar crosses parallel his left eyelid. Allen earned this unusual scar from Mana Walker after turning into an Akuma. The scar also gave him his Cursed Eye, allowing him to distinguish humans and akuma, as well as the human souls bound within.

However, when Mana’s presence activated the next level of his cursed eye, the pentagram in the left side of his forehead also changed as the inside of the pentagram became filled in as opposed to the earlier outlines.

Allen has a tendency to wear hoods and hats to cover his hair and gloves and long-sleeved shirts to keep people from seeing his arm. His left arm houses his parasitic Innocence, from his shoulder down to his fingertips. Initially, his arm appeared red and full of pulsating veins however, after using his Crown Clown for the first time, the skin around his left arm became darker and scaly. Additionally, his fingernails turned black with arrow-like symbols running from his shoulder blade.

However, it has been revealed that Allen Walker’s natural hair color was red or reddish-brown. In an apparent case of Marie Antoinette syndrome – where extreme shock or trauma suddenly causes the hair to turn stark white, named after the French queen doomed to death during the French Revolution – Allen Walker’s hair also turned into white due to shock from reviving his adoptive father Mana as an Akuma and having to destroy him with his own hands. In a conversation with Timothy Hearst, Allen revealed that he tried to dye it a couple of times but eventually gave up as it returned to its silvery white hue.

Is Allen Walker Dead

Near the end of the Volume 22 of the manga, after being officially branded as a Noah, Allen creates his last Ark and leaves the Black Order, disappearing into the doorway which then collapses after him. Before leaving, he told Lenalee that he loves everyone and that he will remain an Exorcist. Three months later, Marie and Lenalee were sent to France on a mission and chanced upon Yu Kanda. There, they find Allen under the guise of a wandering clown. Allen currently fights against the memories and consciousness of the 14th Noah in the company of Yu Kanda and Johnny.

Allen Walker’s Golem

Usually accompanying Allen Walker is a rather peculiar golem, Timcanpy, who was originally owned by his master, Cross Marian. While Allen initially was initially looking after his master’s golem, Cross later admitted that he had always planned for Allen to inherit his golem.

Timcanpy is a small, golden spherical golem with four legs, with the front two used as “fingers” for picking up items or communicating. He also has a long tail ending in what appears to be a thick spiral and two golden, feathered wings. A cross fleury symbol is at its “face” with two small horns at the top. What sets Timcanpy from the standard issue golems is that he appears to be biological in nature, as opposed to the mechanical nature seen in other golems. While he has been damaged or reduced to fragments, nothing which resembles bionic organs are seen but Timcanpy has appeared with a mouth, including teeth and tongue.

During his first appearance, Timcanpy appeared the size of a ping pong ball but steadily grew during the course of the story. At the North American Branch, he grew rapidly large but later found out that Timcanpy can be asked to revert to his usual small form.

Allen Walker Stat Sheet

Allen Walker’s stats are as follows. His initial stats are taken from the D. Gray-man Official Fanbook Gray Ark, while the current stats are from the Official Fanbook Gray Log.

Combat Ability55
Extra Statistics

Allen Walker Innocence


A parasitic-type Anti-Akuma Weapon residing in the cross-shaped gem-like piece of Innocence embedded in Allen Walker’s left hand. This piece of Innocence has taken over Allen’s entire left arm, covering his own with foreign tissue which has merged symbiotically with his own arm and is accepted as a part of his own body.

Cross α (alpha) – The first form of Allen Walker’s Innocence shown in the series which strengthens his left arm at takes an appearance of a large adamantine claw which glows from his shoulder blade joint. When invoked, Cross Alpha can be manipulated to grow large, as Allen did when grabbing the Exorcist Suman Dark, after he morphed into an unbelievably huge Fallen One. While the Cross Alpha has a strong defense against Dark Matter and Akuma-based attacks, other pieces of Innocence can damage this form as shown when Yu Kanda used his Mugen and dented Allen’s arm. The same can be said when Krory’s bite marks were left on the side of his hand.

Cross Grave – The power of Allen’s Innocence can be channeled into a beam of light at the first Invocation which leaves a cross-shaped light behind each target hit. It is capable of hitting and destroying multiple Level 1 in a single blow.

Cross β (Beta) – The second form changes Allen’s arm into a large arm-cannon, with each of his fingers acting as glowing energy spike surrounding the “barrel” of his cannon. This form is more for offense, capable of being used in both melee and ranged combat. The drawback is that it uses more energy.

Cross Paling – The second invocation causes Allen’s arm to shoot rod-shaped stakes of energy. These stakes are made up of hard-light energy generated by the Innocence, allowing them to be planted in the ground as fencing or be shot in a volley towards the enemy.

Cross Spear – An alternative use of the Cross’ second invocation where a stake of hard-light Innocence energy is maintained and held by Allen’s left arm and be used to block and slash, similar to a sword of light or a light saber.

The Cursed Eye

Aside from the piece of Innocence embedded in his left arm, the reverse star-patterned scar running down the left side of his face has cursed Allen’s left eye with the ability to see the human souls trapped inside Akuma forms. Allen mentioned himself that it is “just like an Akuma” since it continuously evolves.

Level 1 – The first version of the cursed eye manifests as a black and red ringed iris against a black sclera which activates automatically in the presence of Akuma. It allows Allen to see human souls trapped inside the Akuma. It was damaged when Allen watched a Level 2 Akuma self-destruct in front of him and caused his eye to bleed.

Level 2 – During the encounter with the exorcist Arystar Krory and his lover-turned-Akuma Eliade, Allen’s cursed eye evolved and changed appearance. It now appears similar to his Level 1 but with the presence of a cogwheel-like monocle with gray transparent lens. This eye now allows Allen to pinpoint the exact location of an Akuma even when hidden behind obstacles which would otherwise make it invisible to the naked eye. Another notable improvement in his ability is that Allen can now see even the lost souls long-trapped inside an Akuma.

Level 3 – During the fight with Alma Karma, Allen’s eye evolved into its Advanced Form. With the lens of the cogwheel monocle turning red and the pupil within his left eye showing a reverse pentagram.

Crown Clown

When invoked, this new form of Allen’s Innocence takes the form of an armor, covering his body including a white-hooded owl and long sleeves – all made up of energy from the Innocence. A masquerade mask covers Allen’s eyes, with the mask appearing in different designs. Also, Allen’s usual hairstyle changes from flat to a spiky rear when the hood is down. Similar to his first form, Allen’s Innocence maintained its sentience and can offer advice or strategy during his battles or even go as far as to move or control Allen’s body in case he is disabled or incapacitated. When inactive, the Innocence reverts to a black pattern up his arm to his shoulder with a tattoo on his left arm.

The Crown Clown manifested some time after Tyki Mikk totally destroyed Allen’s Cross, with the remaining fragments of Allen’s Innocence floating around him in a haze-like form which kept him from dying. Allen then made several attempts to reconnect with his Innocence, but to no avail until his fight with Thread when the remainders of his Innocence responded to his will and adapted a new form.

Cross Grave (Crown Clown Form) – The evolved form allows Allen to crucify targets simply by etching a cross on them using his left arm. This form can easily defeat a Level 3 Akuma by drawing a cross using a single talon on Allen’s arm. Also, a shield can be generated by drawing the same cross in the air.

Crown Belt – The cape from the Crown Clown separates into a webbing of pure energy used to grab and hold objects, restrict opponents, or create hard-light spikes for defense or impaling foes. The Belt can also slip from the Clown’s sleeve and form a glove on Allen’s right arm. Lastly, these webbings of Innocence energy can wrap itself around Allen Walker and manipulate him, similar to a puppet, as demonstrated once when Allen was unable to move due to his injuries.

Crown Edge – A ranged attack where a volley of crown-shaped rings are fired from the clawed fingers of Allen’s left arm.

Edge End – When Allen’s left arm is fully invoked, he releases a large swipe which damages everything in its path with raw destructive power.

Sword of Exorcism

Upon exceeding a synchronization rate of 100% with his Innocence, Allen Walker can transmute the entirety of his cursed left arm into a huge broadsword with black/dark gray cross pattern embellished in both of its faces, connecting directly to the edges of the broadsword with the same color. The Crown Clown usually makes up for the transmuted left arm by covering it with a black cloak.

The Sword of Exorcism can exorcise Akuma and Dark Matter from any opponent it strikes without dealing damage to the human host. Therefore, Allen can attack the Noah within the members of the family without harming their human bodies. When used against Akuma from Level 1 to Level 3, the enemies are destroyed in a similar fashion as the Cross Grave, with the lingering glowing cross at the back of the Akuma. For Level 4 Akuma however, the sword can still deal damage although it does not instantly eliminate the enemy. Also, Allen has shown the ability to recall the Sword back to him via telepathy in case it gets separated from him.

Lero, the rare golem used by the Earl of Millennium, noted that the Sword of Exorcism is similar in design to the sword of the Earl, albeit the colors are inverted.

Death Orbs – When Allen uses the Sword of Exorcism, he creates a series of large, spherical explosions. This move, however, quickly drains Allen after use.

Allen Walker – Quotes

  • (To British Inspector): “Have you heard of exorcists? They specialize in destroying Akuma.
  • (To Yu Kanda): “Kanda… although what you say is true, I want to become a destroyer who can save.
  • (To Yu Kanda): “Because I am a small man, my heart is moved by what’s in front of my eyes, not by what the world needs. I just can’t abandon what’s there in front of me. I want to protect everything I can!”
  • (To Bak Chan): “God? I don’t care about that. I…! I’ve made my own oaths! To myself, that I would destroy the Akuma…! To my friends, that I would fight alongside them! To this world, that I would save it! To my father, that I would keep walking till the day I died… I MADE AN OATH TO THEM ALL! Open up…! Damn it… This is the only path I can take… so that I can feel alive.”
  • (To Moor Hesse): “Akuma is the name of the weapon. It is a weapon made by The Earl of Millennium that target human beings. That is “Akuma”.
  • (To Mana“I swear…I won’t stop no matter what. I’ll keep on walking as long as I live.”
  • (To Cross Marian“When Mana said he loved me, did he mean me or…? Which was it…?”
  • (To Cross Marian“I swore to Mana, That I’d never stop no matter what, that I’d keep walking until I died, I’m the one who swore!”

Allen Walker History

Allen Walker was an abandoned child presumably sold to a traveling circus, in the hopes that his disfigured left arm be used as entertainment by being a freak show. However, the young Allen refused to be displayed as a freak and had taken on odd jobs in the circus in order to survive, despite his left arm being deformed and generally unusable. As an abandoned child sold to the circus, he did not even had a name as was instead called “Red,” because of his left arm and the color of his hair then.

Allen Walker managed to survive in silence largely due to most of the circus shunning and ignoring him. However, Cosimov the clown took pleasure and hurting Red and would often take out his frustrations and mistakes on the young boy. Despite the beating he received, Red managed to make a friend out of the dog owned by the new circus clown. Cosimov’s envy towards the new clown caused him to try and kill the dog by coercing Red to mix glass shards into the dog food. Red refused to participate, and was beaten up by the sadistic clown.

One Christmas day, Red found the dog dead outside the circus. Its owner, the clown, Mana Walker, was in grief in finding his beloved dog beaten to death. It was then that Red learned the name of the dog, “Allen.” When the child asked the new clown why he didn’t cry for the deceased dog, Mana answered that he would not cry nor take revenge for it would create a cycle of sadness in which the Millennium Earl thrives. As the two formed a new friendship, Red began performing with Mana which pushed Cosimov to admit that he killed Allen. Red, consumed by anger, rushed to attack Cosimov but Mana took the blow instead. Mana tried to advise Red not to retaliate because it will only bring about more sorrow. However, Red was furious at the notion that Mana would take the blow for someone like Cosimov and continued to attack Mana until he was unconscious.

In the middle of the trouble, Cosimov led the troupe to believe that Red was behind the death of Allen and was thus put into a cage. It was then that the Millennium Earl, with a legion of Akuma, attacked and killed almost everyone in the circus. Red found Mana after the attack, bloody and driven insane. Feeling that he must have caused it when he beat Mana, Red was overcome with guilt. As Mana continued to call Red “Allen,” Red swore to repay his fault by staying beside Mana and even took up the name of Mana’s deceased dog. Then they traveled together as father and son, as Mana and Allen.

Shortly after, Mana suddenly passed away and caused immense grief for Allen. The Millennium Earl noticed this and manipulated Allen into bringing his adoptive father back. Once Mana realized that he had been brought back as an Akuma, he scarred the left side of Allen’s face – leaving a Pentacle scar – and cursing Allen’s left eye. Afterwards, Allen gained the ability to distinguish human souls within Akuma bodies and inadvertently activated the piece of Innocence that was in his left arm – turning into an anti-Akuma weapon which immediately destroyed Mana’s Akuma form. Before Mana disintegrated, he told for the last time that loved Allen with all his soul. The grief, sorrow, and trauma from his father’s last words turned Allen’s red (brown in the anime) to rapidly turn white.

Then, a General of the Black Order, Cross Marian, approached the devastated Allen and took him in. Cross encouraged Allen, and nursed him back to health at the monastery together with Barba and Mother. Allen managed to regain his senses and his will to live on after hearing cross mutter Mana’s words, “Don’t stop, keep walking.” While Allen started talking and responding again, he was no longer the rude and brash kid, rather seemingly imitating Mana with his politeness and overall kindness. Cross has also introduced Timcanpy, his own golem, to Mana to accompany him and to see if they can be friends.

Allen Walker then spent the next three years training under the guidance of Cross Marian. He vowed to become an exorcist of the Black Order, in hopes of atoning for what happened to Mana.

Allen Walker’s Relationships

Cross Marian – Cross is the master of Allen Walker who also took custody of the boy after Mana Walker’s death and subsequently trained him to become and exorcist. However, Cross is often portrayed as weird, if not outright dangerous, as a mentor for Allen. Three months prior to the start of the story, Cross knocked Allen out with a hammer and left him to find the Black Order. Also, as stated in the D. Gray Man official fan book Gray Log – Cross put his student through a rigorous training regimen. Lastly, Cross has accumulated huge amounts of debt which Allen had to repay, driving the young Walker to gambling.

However, it was revealed that Katsura Hoshino that Cross always makes fun of his apprentice, such as calling him “idiot apprentice,” to have Allen show his dark and snarky side, as opposed from the kind and courteous persona Allen projects in front of others. As a result, Allen never speaks highly of cross, experiences mild panic attacks at the mention of his master’s name, and even experiences nightmare at the thought of meeting his master.

After Mana Walker died, Cross nursed Allen back to health – feeding, cleaning and motivating the unresponsive child until he recovered. While it was later shown that his true motivation was to revive the 14th Noah, he also showed genuine compassion towards Allen. He tried his best to give Allen a chance to live his own life.

Lenalee Lee – She is one of Allen’s first friends upon joining the Black Order. She is about a year older than Allen and is appears to be more mentally and emotionally mature. She has shown the ability to stop Allen and Kanda from fighting. Lenalee has taken it upon herself to make sure Allen does not harm himself from overexertion, given Allen’s nature towards self-sacrifice plus the burden of his left eye and his parasitic-type Innocence.

It was Lenalee who first welcomed Allen into the Black Order, even sharing most members consider it as their Home. Also, after Allen’s first mission in Mater, it was Lenalee who welcomed him back with a smile, even thinking to himself that she is so cute.

During the Rewinding Town Arc, Allen and Lenalee demonstrated their compatibility both in and out of fights, even telling each other their stories. However, their first argument came when Lenalee stopped Allen from sacrificing himself in an attempt to save a self-destructing Akuma. Lenalee ignored Allen until he apologizes for lashing out at her, eventually making her cry since she felt she was not treated as a friend.

Later on, Lenalee started seeing visions in her dreams of the Black Order lying in ruins and seeing Allen’s lifeless corpse slowly sinking into a dark pool. Allen will eventually share the same vision after Tyki Mikk’s attack. Also, the two apparently share a connection as when Lenalee fought Eshi, Allen hears Lenalee’s voice inside his consciousness and a vague picture of the ocean coinciding with what he physically sees. After Lenalee asked Allen what “the world” means, explaining that she considers him an important part of her “world,” since they are comrades. As a result of this newfound understanding, Lenalee defeated Eshi and Allen truly understood his Innocence.

Yu Kanda – Kanda is Allen’s fellow Exorcist in the European Branch of the Black Order and his partner in his first mission. Over the course of the series, Kanda has been shown to be one of the few people who can drive out Allen’s rage and break through his kind and gentlemanly facade. From the first time they met, their opposing attitudes and beliefs caused them to almost always fight each other. While Allen appears courteous, kind, and optimistic, Kanda on the other hand is cold, tactless, and even cynical. Kanda often calls Allen “Moyashi” (beansprout), and Allen calls Kanda “Bakanda” (stupid Kanda) in return.

Mana Walker – He adopted Allen Walker from the Circus, acting as his foster father. However, shortly after he suddenly died, Allen was manipulated by the Millennium Earl to bring him back – albeit in Akuma form. He was then killed by Allen himself using the Innocence in his left arm, but not before Mana cursed the boy’s left eye.

Since Mana was the first person who treated Allen (who was known as Red back then) with compassion, they have formed a bond strong enough for Allen to call his soul into an Akuma. Mana’s own motto, “Don’t stop, keep moving forward,” would eventually be used by Cross Marian to redeem Allen from his state of hopelessness and would eventually be his own words to live by.

Nea D.Campbell – Nea is Mana’s twin brother and is the 14th Noah trying to take over Allen’s body. In the latest story arc, his attempts to possess Allen Walker is the reason Allen was forced to leave the Black Order after he was branded as a Noah himself. While Allen somehow wishes to understand the intentions behind Nea’s actions, he fears that opening himself up to Nea might cause him to lose his own identity.

Earl of Millennium – As an exorcist, Allen has vowed to stop the Earl of Millennium from turning everyone into Akuma and bring about the end of the world.

Allen Walker Voice Actors

Who voice Allen Walker?

In the original run of the Japanese anime series (2006 – 2008), voice actress Sanae Kobayashi was cast for the role of Allen Walker with Ayumu Murase voicing Allen in the 2016 anime, D.Gray-Man Hallow.

Voice actor and director Todd Michael Haberkorn voiced Allen Walker in the FUNimation English Dub while Luci Christian voiced the younger version of Allen.

Allen Walker Cosplay Gallery

D.Gray-man FAQ (Spoiler Alert)

No. Near the end of the Volume 22 of the manga, after being officially branded as a Noah, Allen creates his last Ark and leaves the Black Order, disappearing into the doorway which then collapses after him. Before leaving, he told Lenalee that he loves everyone and that he will remain an Exorcist. Three months later, Marie and Lenalee were sent to France on a mission and chanced upon Yu Kanda. There, they find Allen under the guise of a wandering clown. Allen currently fights against the memories and consciousness of the 14th Noah in the company of Yu Kanda and Johnny.
Allen Lenalee farewell
Allen and Lenalee share a last farewell before Allen leaves into the Ark after being declared a Noah.
The Heart of Innocence is a piece of Innocence believed to be the source of the power of all other pieces of Innocence. So far, Lenalee Lee and Allen Walker have been suspected of being the hosts of the Heart of Innocence as their respective pieces of Innocence have protected them and saved them from harm on separate occasions. However, Allen’s case as the owner of the Heart of Innocence is questioned given the attack by Apocryphos. Furthermore, the Millennium Earl believes that someone does own the Heart of the Innocence and is somehow causing the other pieces of Innocence to exhibit particular traits so as to create what he called a “dummy Heart.”
Heart of Innocence Manga
The Heart of Innocence as it was first shown in the manga.
The answer is both yes and no, depending on how the succeeding chapters will clarify the matter. In Night 219 of the manga, the Millennium Earl reveals to the Nea-possessed Allen Walker that Mana and Nea are the reincarnations of the original Earl. The confusing part is that the current Earl told Allen that Mana was the one behind Nea’s attempt at assassinating him. Adding to the confusion is the current Earl’s dislike at Nea’s attempts at calling him Mana D. Campbell. This intriguing reveal was cut short when agents of the Black Order attack the Earl. 
As for the piece of Innocence embedded in Allen Walker’s left arm, it is not yet fully revealed how the shard got into the boy’s arm. However, he started activating the Cross form of his Innocence after his attempt at bringing Mana back to life, largely in part due to the Millennium Earl’s manipulations. As Mana scarred the left part of his face and granted him the cursed eye, his left arm also evolved and defeated Mana in Akuma form. His weapon changed form after Tyki Mikk shattered his Innocence in China. He was able to awaken the new form of his Innocence during his fight with a Level 3 Akuma together with Bak and Fo. Allen Walker was able to reach and exceed his critical point, the point of 100% synchronization and was able to summon the Sword of Exorcism against Tyki.
In Volume 17 of the manga, Allen learned that Cross Marian was tasked to watch over Mana, the brother of the Noah family traitor only known as “The Fourteenth,” or at least until the traitor returns. Also, it was revealed that Allen was supposed to be the host body needed for the revival of the 14th Noah. However, the presence of the 14th Noah, Nea D. Campbell, started awakening inside Allen’s body when he was stabbed by Kanda’s Mugen. The awakening was put in a temporary stop thanks to Mana’s curse. After using the Ark to transport the Akuma holding the soul of Yu Kanda’s lover, Allen vows never to allow the Order or the Noah to interfere with him anymore. Subsequently, he has been officially branded as a Noah by the Order. 
Allen Walker earns the new form of his Innocence, God’s Clown, also known as the Crowned Clown, in the 70th Episode of the anime. Entitled “God’s Clown,” the episode sees Allen start to disintegrate during the battle with a Level 3 Akuma. When the Akuma turns on Bak and Fo, Allen became enraged and vowed to save humans with his right hand and destroy Akuma with his left hand. His new form easily defeats the level 3 Akuma and shows Allen Walker with a white glove on his right hand, a sleek black left arm ending in arrow-like talons, and a white hood with a masquerade mask. The Crowned Clown was teased at the end of Chapter 83 and fully revealed in Chapter 84 of the manga.
Allen Walker's left arm is actually made up of Innocence. To put it into perspective, the piece of Innocence Allen has is the glowing cross-shaped jewel in the back of his left hand. Furthermore, the cells in his left arm - from his left shoulder down to his claw-like fingertips - are foreign tissues created from the Innocence taking over his original arm since he was bestowed with a parasitic-type Innocence as opposed to Kanda's sword Mugen and Lenalee's Dark Boots, both of which are equipment-type pieces of Innocence and are completely detachable from the user.
In chapter 56 of the manga and episode 56 of the D.Gray-man anime, it was shown that the Noah Tyki Mikk met Allen walker on a mission from the Millennium Earl to eliminate a list of people related to "a certain man." It was here that Tyki attacked Allen and shattered his left arm to verify if it is the fabled Heart of Innocence - since destroying the Heart would also destroy Suman Dark's piece of Innocence in his possession. Afterwards, Allen tried to recover his Innocence which now manifests itself as a haze surrounding him. Allen finally managed to restore his Innocence in a new form in the 70th episode of the anime, titled "God's Clown." In the manga, the new form of his Innocence was teased by the end of chapter 83 and fully revealed in the following chapter. The Crown Clown was awakened as a response to Allen's resolved to save both Akuma and mankind. Ep 56 - shattered arm Ep 70 - crown clown Ch56- shattered arm Chapter 83 and fully revealed in Chapter 84 of the manga - crown clown
During the battle between Allen and Tyki, Tyki Mikk was able to inflict damage on Allen's new arm. However, he explains to Tyki that power comes from the Innocence but what makes him deadly is the exorcist's heart within him. With this, he was able to will the Crown Clown back into existence. As Tyki attempts again to pull out Allen's heart, the exorcist reaffirms his vow to save humans and members of Noah as well. It was at this point that Allen reached a 100% Synchronization Rate, his critical point. With this, his left arm was transmuted into a huge sword later noted by Lero as being similar to the sword of the Millennium Earl himself. This is the Sword of Exorcism which Allen will first use to remove the Noah from Tyki.. The Sword made its first appearance in the 87th episode of the anime and on the 12th volume of the manga. 
This is shown in the 92nd episode of the D.Gray-man anime, entitled "Shadow of the Player." After Tyki was defeated in his awakened form, thanks to General Cross, both Allen and Timcanpy were sent into the secret room of The Fourteenth. Where a silhouetted image from the mirror calls Timcanpy, "My Timcanpy," and invoked the golem's hidden musical score. Allen inexplicably learns to play the White Piano with Timcanpy's score as the guide, and with his wish to save everyone, he was able to control and also restore the Ark as well as the individuals within it.
While there is no exact answer explicitly shown in either the anime and the manga, the series of events between Road Kamelot and Allen Walker narrows the possibilities:: Road first appeared in Chapter 18 of the manga and in Episode 9 of the D.Gray-man anime, as she was tasked by the Millennium Earl to find the Innocence causing the time to rewind during The Rewinding Town Arc. She chanced upon Allen and Lenalee in a battle with three Akuma in a restaurant. They meet again during the Noah's Ark arc, and this is noteworthy because Road suddenly kisses Allen as soon as he walks into the dining hall at the topmost tower of the Ark, to the surprise of everyone else. However, there is no mention that Road is aware that Allen is the host of The Fourteenth. Next is at the Seed of Destruction Arc, where the Millennium Earl is already aware that Allen is the host of the 14th Noah. As soon as the Earl realizes that Nea's host is in danger of the Apocryphos, a special sentient piece of Innocence which aims to absorb Allen Walker into itself, he sends both Tyki Mikk and Road Kamelot to Allen's cell. Apocryphos continued hunting Allen, who insists that he will not join the Noah family. As Tyki returns to stay and fight Apocryphos to allow Allen and Road to escape, Allen started disintegrating and as Tyki forces him to choose between the Exorcists and the Noah, the Innocence and the Dark Matter, Allen laments that he only spreads confusion and sorrow wherever he goes. It was at this point that Road regains consciousness and tells him, "Don't stop. Keep walking." She notes that these are Nea's last words to Mana, and the Nea fought for his brother. She then asks Allen to keep it a secret before completely fading away. Since Road is the only Noah, together with the Millennium Earl, to survive Nea's attacks 35 years ago, it can be assumed that she knew Allen was the host of the 14th around the same time the Earl did too. While the first instance of Road figuring out Allen's identity is yet to be revealed, by Night 205 of the manga and Episode 12 of the D.Gray-man Hallow anime confirms that she was indeed aware of Allen's true nature.
Road Kamelot fadefs
A teary Road Kamelot fades into nothing after telling Allen Nea and Mana's words, to keep walking.
While the Earl initially knows and remembers Allen as one of his victims whose sorrow and strong bonds was enough to summon a soul into an Akuma doll, their relationship has grown more complex as more details about Allen and the Earl are revealed. The Millennium Earl is most likely attracted to Allen Walker because he is the host of the 14th Noah. If anything, the Earl is now extending the same affection towards Allen as he did with Nea. Upon learning that Allen is the host of the 14th Noah, Nea Walker, the Earl asked Allen to join the Noah Family, usually through Tyki or Road. This is taking into consideration that 35 years before the start of the story, Nea attempted to kill the Millennium Earl.