Overdrive

The Overdrive, also known as the Forbidden Move, is the evolved form of Ancient Gear in which their full powers can be released.

Summary
Azazel claims that Overdrive is a "bug" in the system created by the God of the Bible, which can upset the balance of the world and bring the world into overdrive thus given the name Overdrive.

The Overdrive is initially considered a forbidden power by the Five Factions. It is known as the ultimate state of activation for a Ancient Gear.

Overdrive is often triggered by high emotions combined with a change in the heart or spirit of the wielder. It can also be activated when the user is faced with a disadvantageous situation, such as the time when Arthur had to go up against the corrupt Mordred who was wielding both Excalibur and Caliburn.

According to Azazel, the possibilities of the Overdrive can be divided into three categories. The majority of Overdrive, including the Sub-Species, could be placed under the Crest-Drive. The Crest-Drive is classified under strengthening, evolving to a point of transformation. By pursuing the arrogance of themselves and the Ancient Gear, one can further evolve the Overdrive creating a fusion state with their Sacred Relic to produce the Abyss-Drive. The third type, Glitch-Drive consist of the Overdrive that couldn’t be categorized under the previous two categories due to their sudden variation, and is considered as exceptions among exceptions.

Abilities
"Ancient Gears change and evolve while using the feelings of the possessors as a key. But there is a different territory to that. When the feelings and the wishes of the possessor does a dramatic change that it changes the flow of this world, the Ancient Gear reaches it. Yes. This is……Overdrive."

- Ddraig to Arthur Pendragon

The Overdrive is the most powerful manifestation of all Ancient Gears in which the possessor's feelings trigger this evolution. Once reached, the Overdrive can be entered again far more easily than the first time. With proper training, it can be maintained for longer periods of time, as with the case of Vali. While initially Arthur, Lancelot and Sebastian could only maintain it for short periods of time, undergoing intense training helped them improve this time. When first introduced, Vali could maintain his Overdrive for a month.

As revealed in the short story "Vampyre in Wonderland", the Overdrive can also be lost, as with the case of Marsilio of the Hero Faction, who was discovered to have lost his Overdrive ability after he was sent to Hell. The reason is quite possibly due to his feeling of "satisfaction" since he was able to retaliate against the Pendragon group. This means that similar to how a change in one's feelings can "unlock" the Overdrive ability, another change in the opposite manner could have the reverse effect.

Crest-Drive Overdrives
The Crest-Drive is the regular state of Overdrive through strengthening and the user experiencing a dramatic change in their spirit. It consist of a Ancient Gear's original Overdrive. It is the most common state of Overdrive. The Sub-species Overdrive also consist of this category. The Sub-species creates a different form than the actual ones. Sub-species have a tendency to take the form of the user's desired ability in addition to the original. The method to attaining a Sub-species is currently unknown but it seems to involve the user's personality.

Abyss-Drive Overdrives
The Abyss-Drive is a advanced form of Overdrive. By desiring to further improve oneself after attaining the Overdrive, it's possible for the Overdrive to undergo further change. Tobio Ikuse awakened the Perfectus Tenebrae Lykaon et Fortis Densus Laelaps by further polishing the Night Celestial Slash Dogs and Tristan's Sun-Eater roi Que les Règles Sous la Mer is considered an Abyss-side by him completely dominating his Ancient Gear. Vali Apollyon's Caesar Juggernaut Overdrive is also considered an Abyss Overdrive due to Vali attaining it by sealing the past wielders of Divine Dividing.

Glitch-Drive Overdrives
The Glitch-Drive is a irregular and unique form of Overdrive. This class of Overdrive belongs to a category that can't be classified under any of the known category due to being an irregular, either due to sudden change or it being a combination of the known categories. Arthur's Incursio and Cardinal Crimson which is made possible through the Transfer Pieces, Lancelot's Overdrive is formed through the combination of his 7 Ancient Gear into one are among the known examples of this category.

Counter Drive
Counter Drive, also known as Phantom Move, is the Artificial Ancient Gear version of Overdrive, allowing the user to evolve their Artificial Ancient Gears and use their full abilities. Unlike the normal Overdrive, which is merely the unleashment of power that destroys the balance of the world and sends it into overdrive, the Counter Drive is the opposite. Compared to genuine Ancient Gears, which are already stable by nature, this state is attained by the possessor's power being used to forcibly stabilize the Artificial Ancient Gear

Known Overdrives

 * •  Zenith Longinus
 * → Deus' Silver Will (Holy Spear that Incarnates the Pure Whit Night)
 * → Dawn Polar Night Longinus Götterdämmerung (Twilight Holy King’s Heavenly Artillery Enveloped in Brightness Which Brings the Dawn of the Polar Night): Cao Cao's Sub-species Overdrive. It creates a ring of light and seven orbs around him. Each orb providing him with a special ability, and the Zenith Longinus is still a spear which he can use.


 * •  Tempest Prophet
 * → Elementi Violenti Illimitati del Messaggero (Four Violent Elements of the Messenger)
 * → Flagello dell Arcobaleno Bianco, i Raggi di Speranza (Inevitable Punishment of the White Holy Angel's Rainbow, Shining Star Rays of the End): Marcello Pasolini's Sub-species Overdrive of Tempest Prophet. In this form Marcello possesses 12 golden wings, and five halos, 4 above his head and 1 large one on his back. Marcello creates countless bubbles, trapping his opponents within them. Marcello then controls the climate within these bubbles to attack those trapped within, creating Intensely swirling flames, violent hurricanes, freezing cold air which freezes everything, and vicious torrents of lightning.


 * •  Annihilation Maker
 * → Bandersnatch and Jabberwocky: Alice's Sub-species Overdrive. It creates thirteen gigantic monsters (one Jabberwocky and twelve Bandersnatches). Both type of monsters have the ability to create smaller copies of themselves, while the Jabberwocky has enhanced regenerative abilities allowing it to heal rapidly from any external injury and reattach severed limbs.


 * •  Paradise Lost
 * → Paradise of Creation (Poltergeist Utopia of Mist): creates a much stronger barrier than the Paradise Lost and it can also create numerous barrier-related devices.


 * •  Boosted Pump
 * → Red Scale Mail (Armor of the Red Dragon Emperor): covers the user in a red armor that embodies the power of the Red Dragon Emperor.


 * •  Divine Dividing
 * → White Scale Mail (Armor of the White Dragon Emperor): covers the user in a white armor that embodies the power of the White Dragon Emperor.


 * •  Incinerate Anthem
 * → Versteinerung Mass Ceremony (Ritual Flame Verdict of Mass Petrifaction): Arthur Pendragon's Sub-species Overdrive. It allows the Arthur to petrify a mass amount of people, including Archangel-class Seraphs.


 * •  Sindone Martyrdom
 * → Incinerate Antiphona Calvario (Blazing Verdict by the Final Judge): Walburga's Sub-Species Overdrive. Its characteristics and capabilities may vary depending on the crucified soul Walburga imbues it with. The forms are able to move independently from her and acts like an independent-avatar type.
 * → Lovely Heavenly Angels (Purple Flame and Love Angels): Bastinda Strada's Sub-Species Overdrive. It creates 3 huge angels (2 males and 1 female representing Charlemagne, Kurze, and Bastinda) covered in purple flames. The angels can combine with each other to become one large angel.


 * •  Absolute Dawn
 * → Alba di Assoluto Argento Mondo (Snow World Believed to be Eternal at Dawn): Lavinia Reni's Overdrive. It has the ability to create a strong blizzard that can make a distinction between between friend and foe.


 * •  Sephiroth Bonsai
 * → Sephiroth Longinus Ein Sof (Holy Tree of the Ten Pure Night)
 * → Kabbalah Hyperion Wraith Trinity (Traditional Tree of the Ten Elemental Hanging Gardens held by the Holy, Demonic and Divine Spirits): Kurumi Nonaka's Sub-Species Overdrive.


 * •  Aether Providence
 * → Aethereal Shatter Dome (Cracked World Shield that Cannot be Broke): Maes Hughes' Overdrive.


 * •  Canis Lycaon
 * → Night Celestial Slash Dogs (Mad Blade Dog God Fiend of the Glowing Night Sky): Tobio Ikuse's original Overdrive. Tobio transforms with darkness into a humanoid black Hound with nine tails and Jin transforms into a big Black Hound, in this form not only does Tobio gain enhanced strength he can create an innumerable amount of blades, capable of tinging the sky and earth in darkness.
 * → Perfectus Tenebrae Lykaon Fortis Densus Laelaps (Dark Demon Beast of the Abyss, Dog God of the Hero's Eternal Night Blade): Tobio Ikuse's Abyss-Drive Overdrive. He achieved this form after training and becoming accustomed to using his Ancient Gear. By reciting a curse-like chant, Tobio’s entire body becomes covered in darkness, and he takes the form of a humanoid beast clad in darkness and he gains a long and immensely sharp scythe and can also create jet-black gigantic blades from the ground.


 * •  Panthera Nemea
 * → Panthera Nemea Leather (Iron Skin of the Lion King): Regulus Panthera's Sub-species Overdrive. It covers the user in a Golden Lion Armor that highly augments the wielder's power. It also provides him protection from projectile attacks.


 * •  Innovation Imperium + Telos Karma
 * → Transcendental Arrival: Midoriya Kanzaki's Overdrive of Innovation Imperium and Telos Karma. Midoriya's body becomes clad in a futuristic-looking powered exoskeleton.


 * •  Cardinal Buster
 * → Cardinal Bishop Automail Armor (Principal Bishop's Silver Holy Armament): Cardinal Buster's Overdrive.


 * •  Beyond Balor View (Aeon Beyond Balor)
 * → Berolina Invade Beyond the Balor Reborn (Black Beast Master of the Forbidden Beyond Night of True Darkness and Light-Eater): Nanao Tepes' Glitch-Drive Overdrive. It creates an enormous amount of darkness that can engulf a whole town and devours everything (including the mist created by Paradise Lost) and can generate twisted monster of said darkness, while also covering Nanao's body and transforming her into a five-meter-tall monster with a Dragon's head, arms with claws and wings growing from the back.


 * •  Monad Voice (Melody of Will)
 * → Monad Troy the Phantasmagoria Aria (Lustrous Song of the Black Phantom and Judgement of Irresistible Beauty): Helen's Sub-species Overdrive of Monad Voice.


 * •  Blade Borne
 * → Sword of Betrayal (Holy-Demonic Sword of Twin Supremacy): Sebastian Michaelis's Glitch-Drive Overdrive. It allows him to create Holy-Demonic Swords.


 * •  Saint Healing
 * → Twilight Saint Maiden Affection (The Garden Of Love and Charity, held by Holy Midnight Dragon Princess): Elaine Du Lac's Sub-species Overdrive. It takes the form of a Crimson Dragon Armor with black and white jewels that covers her body and has the ability to cover a field with tremendous healing property that can negate any damage from virtually any sources.


 * •  Blade Blacksmith
 * → Blade Knight Mass (Supreme Holy Knight Army): Blade Blacksmith's Overdrive. It creates multiple armored knights equipped with holy swords.
 * → Stake Victim Dragonar (Holy Dragon King of Judgement): Roma Caesar's Sub-species Overdrive. It creates an artificial dragon made entirely of holy swords.
 * → Betrayal Glory Trooper (Supreme Holy Dragon Knight Army): Sebastian's Sub-species Overdrive. Similar to Blade Knight Mass, it creates armored knights equipped with holy swords. It differs from the Blade Knight Mass as Betrayal Glory Trooper's knight's armor are dragon-themed and they reflect Sebastian's speed and technique. Due to his inexperience, the Dragon Knights can only reflect his speed and not his techniques.


 * •  Law Gunsmith
 * → Revolver Soul (Supreme Lone Gunner Army): Law Gunsmith's Overdrive. It creates multiple cowboy-themed armored knights, each equipped with both a holy revolver and a demon revolver.
 * → Rocket Panzer Tank (Great Dragon of Destruction): Doc Holliday's Sub-species Overdrive. It creates an artificial dragon-themed tank.
 * → Fusillade Glory Trooper (Artillery Gunner Army): Zachery Shidou's Sub-species Overdrive. Similarly to Revolver Soul, it creates an army of cowboy-themed dragon-knights each equipped with different types of guns such as pistols, revolvers, machine guns, assault rifles etc.


 * •  Macabre Light
 * →Macabre Black Lights (Ancient Abyssal Dying of the Higher Angels): Sieglinde's Overdrive. Sieglinde's body is engulfed in black-colored holy light, with her gaining four black wings and a halo made of darkness.


 * •  Staring Red
 * → Sterling Red Bolt (Demon-Destroying Arrow of Pure Red Light):


 * •  Hellbent Revenant + Typhoon Innovate + Zero Absolute + Mother Nature's Rose + Terra Arcane
 * → Apocrypha Whisper (Song of the Unknown King): Oliver's Overdrive which combines his five Ancient Gears. It clads him in a iron armor with magma outlines.
 * → Terra Arcane Guardian (Earthquake Guards): Terra Arcane's Overdrive, which creates three stone guardians which the user can control.


 * •  Edge Asura Hand
 * → Grim Edge Dhampyr Ravage (Feast of the Half-Vampyre and Demonic Beast): Charlemagne's Sub-species Overdrive. It creates three extra dragon arms coming out of his back; each doubling his power for a total of sixteen times, with the arms also being capable of generating and projecting barriers.


 * •  Overseers Anthem
 * → Overseers Dream Melody
 * → Oversight Marionette Black Song (Puppet Army of the All-Seer): Guan Yu's Sub-species Overdrive. It allows her to create fifty ethereal puppets, with Athena being able to take control of anyone of the fifty at any time.


 * •  Variant Detonation
 * → Detonation Mighty Comet (Malicious Wave of the Superman) : It creates missile-like protrusions from the user's body that they can shoot with.


 * •  Dawn Reflection
 * → Dusk Reflection Inverted Cross (Demonic Beast Skin of Dark and White Night): Lysandre's Sub-species Overdrive. It creates an armor made out of shadows. It grants the user to become like a shadow, gaining its intangible properties and allowing physical attacks to pass right through him, although the user is still susceptible to most forms of energy (heat/cold).


 * •  Absorption Line + Inferno Black Flare + Sleeping Camo + Delete Field + Kin Vala + Abyss Prison + Snake Web
 * → Malebolge Vritra Promotion (Dragon King's Flame Prison of Guilt): Lancelot Du Lac's combined Ancient Gear's Glitch-Drive Overdrive. It covers Lancelot in a black dragon armor with tentacle-like things growing from it. In this state, Lancelot and Vritra's consciousness is fused into one and Vritra's powers can be displayed more than when using Vritra Coronation.
 * → Valall Shrouded Army (Black Demon Children of the Evil Dragon): Lancelot's Overdrive of Kin Vala.


 * •  Wawel Bones + White Seething Flare + Energia Eater + Vice Claw + Sunk Srebro Brim
 * → Smok Wawelski Promotion (Evil Dragon's Crazy Bone Prison): Garou Fujimaru's combined Ancient Gear's Glitch-Drive Overdrive. Similar to Lancelot's, It covers Garou in a bone-like white dragon armor with bone-like claws and spikes sprouting from it. In this state, Garou and Smok's consciousness is fused into one and Smok's powers can be displayed more than when using Smok Promotion.


 * •  Mirror Alice
 * → Nostalgia Mad Tea Party (Tea Party of Nostalgia): Tsubaki Strauss' Sub-species Overdrive. It creates demons that came through her mirror that each have different abilities.


 * •  Nigredo Shroud
 * → Queen Anne's Dark Revenge: Edward Teach's Sub-species Overdrive.


 * •  Infernal Curtus Snake
 * → Sun-Stream Dimensional Serpent (Mad Fiend Snake King of the Burning Sky): Tristan's original Overdrive. Tristan transforms with light and fire into a humanoid golden and orange serpent with a long tail, scaly skin and claws (similarly to a lamia), and Meliodas transforms into a giant golden Hydra with 4 heads, in this form not only does Tristan gain enhanced strength and speed he can create an innumerable amount of blades and snakes, capable of plunging the sky and earth in flames.
 * → Sun-Eater roi Que les Règles Sous la Mer (Higher Holy Beast of the Sun, Snake King of the Eternal Sky Scale)'': Tristan's Abyss-Drive Overdrive. He achieved this form after training and becoming accustomed to using his Ancient Gear. By reciting a curse-like chant, Tristan's entire body becomes engulfed in flames, and he takes the form of a humanoid snake-beast clad in flames and darkness and can also create jet-black gigantic blades from the ground.


 * •  Vermilion Dragon Lance   (artificial Ancient Gear)
 * → Vermilion Another Down Fall Armor: Vermilion Dragon Lance's burst-state Overdrive. It covers the user in a crimson white dragon armor much like Arthur's and Vali's Scale Mails. It mainly strengthens the user's overall power using Aoqin's power.


 * •  Procellarum Lepus Phantom  (artificial Ancient Gear)
 * → Hyper Phantom Rabbit: Procellarum Lepus Phantom's Overdrive. It coats the user's body in a rabbit-themed armor, that increases the user's speed to such a degree that its quoted as God-Speed.


 * •  Holy Resuscitation
 * → Fourteen Holy Salvation (Salvation from Fourteen Healing Saints): Overdrive that allows user to increased the area of effect as well as a wider range of symptoms that could be cured. If the target was a believer, even a serious illness could be completely cured.


 * •  Sturdy Saint
 * → Sturdy Saint Withstand (Saint's Trial and Next Trial): In this state, the user's defense is enhanced to the point that they can survive an attack equivalent to Tomoe's Cross Crisis after the latter had been greatly strengthened by Crimson Clear Dragonar.


 * •  Dream-Eating Curse
 * → Paraselene Utopia (An Illusion Forever Wrapped): It has the ability to send a targeted individual into a barrier space of his creation (a seemingly parallel world). One of the rarer Overdrive abilities, as it doesn't seem to have direct attack powers, it is often used in conjunction with illusions to create a sense of despair for both the targeted victim (as well as crumbling their mentality) and those from the other world who they share a connection with.


 * •  Chakra Sovereign
 * → Seven Holy Sovereign:

Trivia

 * Currently, the number of Sub-species Overdrive outnumber Overdrives.
 * Midorime based the Overdrive on the Balance Breaker transformation from High School DxD, the Super Saiyan transformation in Dragon Ball Z and the Bankai transformation in Bleach.