Allen is initially rather short, though in the manga he seems to grow as it progresses. He has white hair (from the shock of the curse Mana inflicted) that grows longer and spikier over the series, as well as a red (later seen as purple) scar along his left eye, an injury inflicted by Mana that resulted in his left eye being able to detect the souls of Akuma. Because of his Parasitic Innocence, his left arm is red and somewhat unnatural. Allen's Innocence's form was destroyed in China, though he regains it shortly thereafter and it has since taken a black, more human appearance when deactivated, the skin smoother and no longer plated. Allen wears the standard Exorcist uniform, with a hood and gloves covering his hands. Allen is somewhat slender, but physically fit, with muscle tones not normally seen on boys of his age. He has a rather prominent scar along the right side of his torso caused by an encounter with a level four Akuma. After his training to reclaim his Innocence in China, Allen was given a communicator earring, which continues to be a new part of his wardrobe while it has received modifications several times.
Allen Walker is a very kind and generous person. He is nice, caring, and well-mannered, always polite. He is quite close to his friends, namely Lenalee Lee and Lavi. Always thinking of the lives of others before himself, he often puts himself in harm's way for other people's sakes. After his family had abandoned him because of his strange left arm, he lived at a circus where he performed odd jobs for money. His personality was different in his childhood. He was rude and cold towards Mana, Cosimo, and the other circus members. He would hit anyone who provoked him, and cursed anyone who bothered him. Allen, Mana's dog, was the only animal that cared for him and the only animal that he cared for. After Allen's death, Mana and Allen (who was called Red in the circus) became friends which formed from the bond of the beloved dog. Because of his experience with Mana as well as being cursed from turning Mana into an Akuma, Allen considers Akuma to be extremely important to him. He wishes to soothe the suffering of the Akuma's human soul by freeing it with his Innocence. He always remembers his promise to Mana, to always continue to walk, to move forward.
Allen is seen as a true gentleman throughout his ventures, but he hides the most strife and anger seen through any of the characters in the series. When observing Allen's ventures, he has caused the death and prolonged passing of his adoptive father, Mana Walker, has lost his master, with whom he shared a deep relationship with, was abandoned at birth due to his deformed left arm, and has failed to protect the various characters in the series that he has formed deep bonds with, such as Tapp, whom he felt responsible for his death after the Skulls transformation. Allen has lost those he has truly formed deep bonds with, has pushed himself into an emotional corner with self-blame, and feels like an outcast from the very humans he protects. Even with all of these negative situations constantly being pushed into his face, he continues to use the Innocence that has so drastically ruined his life to protect the world from the Noah and the Akuma.
Powers and AbilitiesEdit
Physical Prowess: Due to his Innocence being largely used for close combat, Allen is noted to be above normal human standards in terms of physical fitness, making him able to perform in seemingly physically impossible workouts and hold back Akuma attacks that are known to take out walls. An example of this extreme state of fitness is it ability to lift his entire body weight on the strength of a single finger. His physical abilities are only increased when his Innocence is activated. Amateur Swordsmanship: After Allen received his Sword of Exorcism, he began training with Kanda to develop his swordsmanship skills, though after losing in a spar he reverted to physical brawling.
Cross Spear (十字架ノ槍（クロス・スピアー）, Kurosu Supiā; Japanese for Chrono Cross Sphere): Also in its second phase of invocation, Allen is capable of focusing the barrel of his Innocence-cannon to generate a spear-like energy paling, which can then be used like a sword.
- Cross (十字架 （クロス）, Kurosu): is a rare, parasite-type Innocence that shares a symbiotic relationship with Allen's body. It appears as a cross-shaped shard embedded in the back of his left hand, which causes his entire left arm to appear red, scaly, and deformed. As a parasite-type, it is capable of both invoking and acting of its own accord, such as when it destroyed Mana's Akuma or regenerated the portion of Allen's heart that was hollowed out by Tyki Mikk's Teez. The name is sometimes incorrectly translated as Cross of God (十字架, Jūjika), a more literal translation of the kanji used.
- Cross α (alpha): The first and most basic form of Allen's Innocence augments his left arm into a monstrous adamantine claw with a supernatural glow at Allen's scapula-joint. At this phase, his Innocence is capable of manipulating its size and shape even to extreme ends, such as when it grew enough to grab the entire body of the mountain-sized fallen one, Suman Dark.
- Cross Grave (十字架ノ墓（クロス・グレイヴ）, Kurosu Gureibu Japanese for Chrono Cross Grave): At the first level of invocation, the Innocence's power can be channeled into one powerful stream, capable of crucifying and destroying multiple Level 1 Akuma simultaneously.
- Cross β (beta): The next evolution of his Innocence occurred during Allen's investigation of "The Ghost of Mater". This evolution takes a more offensive approach, in the form of a massive arm-cannon and his finger becoming some sort of energy spikes. This form is capable of ranged and melee combat; a contrast to the defensive nature of his Innocence's first form.
- Cross Paling (十字架ノ杭（クロス・バリング）, Kurosu Baringu; Japanese for Chrono Cross Pile): At its second phase of invocation, Allen's Innocence is capable of firing volleys of rod-shaped energy palings; these laser stakes are made of hard-light Innocence energy, which enables them to picket the ground and fence in the adversary, or to pile upon them; Allen may also stand atop of the palings. This ability is occasionally mistranslated as "Cross Beam".
- Crown Clown (神ノ道化 (God's Clown) (クラウン・クラウン), Kuraun Kuraun): Allen's synchronization ratio reached a maximum of 83% before having his Innocence destroyed by Tyki. Yet unknown to Allen, the Innocence lingered around as a hazy fog of particles; at the time, a direct reflection of his shattered state of mind. It wasn't until he came to an epiphany that he was able to seize control of his Anti-Akuma weapon once again and achieving his Innocence's true, fully-invoked form. When not activated, his arm is black and meets with his shoulder in a spiraling pattern that ends with tattoo-like emblem.
When invoked, Crown Clown acts as a body-armored Innocence, forming a white-hooded cowl and sleeve of Innocence energy which covers his shoulders and right arm, while his left arm and hand become slender and black, clad in armor and razor sharp claws. A masquerade-style mask is always affixed to the cowl, which takes on various configurations and appearances. This transformation also changes Allen's usual hairstyle from flat to a spiky rear. As before, his Innocence possesses a certain degree of sentience, but as Crown Crown is able to manipulate Allen's entire body like a marionette when incapacitated, or simply assisting in evasive tactics.
- Cross Grave (十字架ノ墓（クロス・グレイヴ）, Kurosu Gureibu): Much more powerful than its previous incarnation, Allen can crucify targets simply by etching a cross upon them with his left hand, effectively annihilating even Level 3 Akuma with a single talon. It can now also be used defensively, generating a shield by drawing a cross on the air.
- Clown Belt (道化ノ帯（クラウン・ベルト）, Kuraun Beruto Japanese for Belt of Clowning): The cape of Allen's cowl is released as a webbing of Innocence-energy that can be used to grasp objects, immobilize opponents, or form hardened spikes to impale enemies. It can also be released from the sleeve and glove on Allen's right arm. The ribbons of energy were once used by Crown Clown itself to wrap around Allen's limbs and control him like a puppet when Allen was too injured to move by himself.
- Crown Edge (爪ノ王輪（クラウン・エッジ）, Kuraun Ejji Japanse for Claw of King-Ring/Circle/Hoop): A projectile attack which unleashes a barrage of crown-shaped rings from the clawed fingers on Allen's left hand.
- Edge End (破滅ノ爪（エッジ・エンド）, Ejji Endo Japanese for Destruction Claw): A swipe of raw destructive power dealt with Allen's fully-invoked claw.
Sword of ExorcismEdit
- The Sword of Exorcism (退魔の剣, Taima no Ken Sword of Salvation): When Allen's synchronization ratio exceeds 100%, he is able to transmute his entire left arm into an exquisite broadsword with a large cross emblazoned on the face of the blade. In doing so, his left shoulder is capped with a cross-shaped emblem, and his cowl usually forms a cloak to cover the missing arm. Once invoked, the blade can exorcise evil from any vessel it strikes without any harm coming to the vessel itself if Allen chooses. If used against Level 1 to Level 3 Akuma, it vanquishes them in the same effect as the Cross Grave attack, leaving a residual glowing cross crest in the wake of the defeated Akuma. However, in the case of a Level 4 Akuma the sword carries a diminished effect. Allen is shown with the ability to telepathically recall the Sword to himself, should it be separated from his body. It is noted that the design of the sword is the same as the Millenuim Earl's except for the inverse of colour, as mentioned by Relo.
- Death Ball (いちた たま, Sendo no Mari) When using the Sword of Exorcism, Allen can create an explosion which he names Death Ball.
- Energy Arc When using the Sword of Exorcism, Allen can release an arc of energy at his target.
The Cursed EyeEdit
In addition to his Innocence, the reverse pentacle that scars his left eye curses Allen with the power to see the souls trapped inside Akuma. He received it after Mana died. The Earl appeared to Allen, offering to revive Mana for him. When Mana came back as an Akuma, he was angry at Allen and scratched him on the left eye, after which Allen's Innocence activated and exorcised Mana. Allen refers to his eye as "Mana" when it heals, evolves and a spirit is seen entering his eye. He comments, saying that it's "just like an Akuma" in the way that it evolves. The Earl has noticed Allen's eye and has made changes to stop the eye's power.
- The Cursed Eye Level 1: The first incarnation of the curse is a black and red ringed eye which is automatically activated whenever Allen is near Akuma. It allows him the power to see the souls trapped inside Akuma. When Allen witnessed the self-destruction (under Road's orders) of the Level 2 Akuma and the disintegration of the soul powering it, his cursed eye bled in pain.
- The Cursed Eye Level 2: During the vampire incident involving the Eliade-Akuma and Arystar Krory, Allen's curse had grown stronger, resulting in his eye undergoing some dramatic changes. Resembling a sort of cogwheel monocle, this new cursed eye enables Allen to pinpoint an Akuma's position even when they are not visible to the naked eye, regardless of obstacles, from a distance of up to 300 meters away. But the most astounding change is that others close to Allen are able to see the lost souls trapped within Akuma as well. After witnessing Allen's 'world of black and white', Lavi comments that the way Allen sees the world 'is like hell on earth'. However, the cursed eye appears to lust for the destruction of Akuma, often causing pain to Allen in the middle of the night by self-activating, as though "it is a sin to be sleeping instead of destroying Akuma". The eye also seems to activate itself even when no Akuma are nearby as long as dark matter is being used, such as when Allen is caught in the Noah Tyki Mikk's vacuum.
- The Cursed Eye Level 3: Advanced Cursed Pentacle Eye: In chapter 198 it was shown that Allen's eye has become more advanced his pupil gaining, instead of the red circles, a reverse petagram.
It is revealed that Allen is the host chosen for the 14th Noah's revival, and was implanted with his memories at some point in his childhood while living with Mana, the 14th's older brother. The memories of the 14th Noah are said to gradually eat away at him until, eventually, nothing will remain of Allen's personality and he will be reborn as the 14th Noah. As a direct result, he has begun to see the shadowy silhouette of the 14th looming over his own reflection. Included among these memories is the power of the Musician, which allowed Allen to enter the 14th Noah's room and assume control of the Ark by playing the white piano within. In doing so, he halted the download of the Akuma egg plant, reconstructed the destroyed Ark and returned those who had previously been lost in its collapse, ultimately claiming it to be used as a tool for the Black Order. This power also lets any wish he wants to be granted, explaining how Kanda, Krory, Lavi and Chaoji come back from a lost dimension--despite Cross saying they were dead.
Cross states that the 14th chose Allen as he was running away with Mana and did not want to let this chance slip by. He also states that he knew both the 14th and Mana, and that the 14th told Cross to take care of Mana and if he died, the 14th would one day return to him (Mana). Another thing he states is that, Mana sort of lost it after the 14th died, leaving Allen to believe he may have not loved him at all - but simply the memories of his brother. Cross also told Allen he would have to kill someone he loved when he became the 14th. Cross ends his meeting with Allen by telling him to listen to the 14th and that there is "another side to this war".
Despite the prediction of his fate, Allen has vows to keep fighting no matter what, that he will not simply give in to the 14th's personality. The Order allows him to continue his duties under scrutiny, but puts restrictions on his Musician abilities. In addition, he is closely shadowed by Howard Link of the Order's special operations unit, CROW who is investigating and reporting his every move.
However, in later chapters Earl reveals that Allen isn't the player or the host of the memories that the 14th left behind, but he is the 14th himself. It is revealed after the 14th connected to Earl while Allen was fighting with the Level 4 Akuma during the Timothy Arc. It hasn't been revealed how the 14th is Allen, since it was disrupted by 14th reappearing and declaring that he will kill the Earl and take his title.
- Allen is technically capable of becoming a General due to hitting critical synchronization to above 100% with his Innocence. The reasons for his lack of General status may be age, inexperience, and/or other factors.
- It is known that Allen can get lost very easily as seen when he was in Mater. Some people also constantly remind him to not get lost.
- In the oneshot Zone it is shown that the beta for Allen was originally a female Akuma turned by Cross by being fused with an Anti-Akuma weapon.
- In the D.Gray-Man Popularity polls Allen placed 1st in the initial poll and 2nd in the next poll losing out to Yū Kanda, and then placing first again in the next.
- Allen's favorite food is mitarashi dango and his hobbies are Making Money and Eating.
- According to Hoshino, Allen is ambidextrous.
- Allen can see very well in the dark almost like "nightvision" he described from training with Cross.
- In D.Gray-Man Reverse Volume 3, it is revealed he never actually had a name and that "Allen" was the name of Mana's dog, which he used as his name later on when Mana had gone insane. He was nicknamed "Red" during his days in the circus because of his arm.