Diabolus Dragon Beast

Diabolus Dragon Beast is the second upgraded form of the Scale Mail and the first dubbed "Transcendental Overdrive", after Arthur borrows the power of Wagyl and Ophis. By syncing the powers of Albion and Apollo with Ophis' help, Vali can activate a similar form.

Summary
The Diabolus Dragon Beast form is first seen in Volume 20 when Arthur finally calmed Brynhildr's spirit, unlocking it with Ophis' help. With it, he was able to overcome Drakon's Ancient Gear Canceller Advanced and quickly defeat him. However, the immense power of the form caused him to painfully collapse after its release and cause several different pains such as vomiting of blood and headaches.

Vali also attains his own version of the Diabolus Dragon Beast in Volume 22 with Ophis' assistance. However, Vali's version is powered by syncing his previously dormant power of Apollo with Albion's own. In the same Volume, after Arthur's battle against Cythraul and the Trihexa Core, Ophis reduces the power of Arthur's Diabolus Dragon Beast and removes the "infinity" aspect in it, successfully eliminating the life-threatening setbacks it previously had.

In Volume 23, Arthur reveals the ability to perform a partial Pseudo-Dragon Beast Deification on his left arm, allowing him to use his Dragon God Aura to a lesser extent with less stamina consumption. With this technique, Arthur can combine his Banishing Shift aura into both Solid Impact Booster and Drago Shot.

In Volume 25, after drinking the miracle drug, Amrita, he became able to maintain his Pseudo-DxDxB Form for 88 minutes in combat and even became able to manifest Ddraig in his true form after the [8] countdown reaches zero as a result of the miracle caused from the drug.

Forms
Diabolus Dragon Beast: Lilith=

Diabolus Dragon Beast: Lilith
  is Arthur's version of the Diabolus Dragon Beast. The armor becomes colored in a both crimson, white and black and adding a second and third set of wings on his back, totalling of six. After the battles against Cythraul and Trihexa, Ophis reduces the power of the DxDxB-L and removes the infinity in it to remove its almost fatal side-effects. This adjusted DxDxB is dubbed Pseudo-Dragon Beast Deification. The form can only be maintained for a maximum of three minutes at a time, but attacking, defending and moving will further reduce this time limit, to the point that usage in actual combat generally amounts to nothing more than ten seconds. After drinking the effects of Amrita, his countdown of his Pseudo-DxDxB changed from ten seconds to eighty-eight minutes, reflected by [88] on his left gauntlet. During his fight with Angra Mainyu, Issei unlocks True-Dragon Beast Deification (真の龍獣神化, Shin no Ryūshishigami-ka), which is described as having Vampyre, Devil, Seraph, Dragon, and God aura. Morpheus and Melionë notes that Arthur's power in this form is even greater than when he was in Pseudo-DxDxB.
 * Longineus Infinity Blaster (ロンギネウス・インフィニティ・ブラスター, Rongineusu Infiniti Burasutā): A further enhanced version of the Crimson Avalon Blaster. Similarly to Cardinal Crimson Incursio, DxDxB's wings contain hidden cannons. These six cannons shoot out a powerful blast of red, black and white aura that can injure even a Super Devil like Drakon and Rizevim to the point of near-death. Initially, due to the unstable nature of Arthur's Pseudo-DxDxB, a single usage of the blast in Pseudo-DxDxB will reduce the time limit of three minutes to ten seconds. After drinking miracle drug Amrita, Arthur has overcome this weakness and can maintain his armor after shooting Longineus Infinity Blaster.
 * Longinus Smasher (ロンギヌス・スマッシャー, Ronginusu Sumasshā): The form is not only capable of this move, but the blast it shoots out has been enhanced with the power of infinity, delivering further damage. It can also be used in tandem with the Longineus Infinity Blaster, fusing the two blasts into an even more powerful attack.
 * Gown Breaker, an new enhanced version of the Arthur's Orgasm Magic augmented by the Diabolus Dragon Beast armor, by using his Dragon God aura, he can halt his target’s movement. While strengthening his left hand he can destroy a female uniform without touching it.
 * Red Dragon Emperor Ddraig Summoning (赤龍帝ドライグ顕現, Sekiryūtei Doraigu Kengen): Due to drinking the miracle drug Amrita, Arthur gained the ability to summon Ddraig into battle after the [10] countdown on the right gauntlet reaches zero.
 * Brynhildr Summoning: After drinking an enhanced version of Amrita, Arthur gained the ability to summon not only Ddraig, but also a mechanical Brynhildr into battle after the {19} countdown on the left gauntlet reaches zero.


 * -|Diabolus Dragon Beast: Phoebus=

Diabolus Dragon Beast: Phoebus
  is Vali's version of the Diabolus Dragon Beast that is achieved through the combination of the powers of Albion and Apollo dubbed Monster Apotheosis by Aži Dahāka. The armor becomes colored in a mix of silver, orange, white and black and gains sixteen mechanical Demons wings and four halos. This form can only be sustained for a short time that has yet to be revealed in detail.
 * Apollyon Compression Divider: Vali releases a burst of silvery-white and jet-black light that instantly compresses anything caught in it to the point of non-existence.
 * Divinity Apollo Driver: An enhanced version of the Boosted Pump's Longinus Smasher. Much like with the former, the armor plates on the chest and abdomen slide open to reveal a cannon muzzle that promptly fires a massive bombardment of silver-white, bright-orange and jet-black aura. When hit directly, this attack is powerful enough to fatally injure Aži Dahāka, an Evil Dragon who had reached Heavenly Dragon-class in power.
 * Dividing Wyvern Fairies: In this form, Vali can detach his wings and shape them into small white Wyverns that can use Divide, Reflect and Half Dimension. The Wyverns are also able to morph into cannons that fire out powerful shots of Apollo's aura. The Wyverns are also able to use Albion's Reduce ability, a deadly poison that can destroy even Gods by cutting down not only their bodies, but also their souls. However, this poison is ineffective towards Wagyl, Ophis, Scarlet Grand and Ddraig.
 * Albion Summoning: Vali gained the ability to summon Albion into battle by performing a chant.
 * Vali: Be resurrected! Vanishing Dragon that dwells inside of me!


 * -|Diabolus Dragon Beast: Vritra=

Diabolus Dragon Beast: Vritra
  is Lancelot's version of the Diabolus Dragon Beast that is achieved through the combination of the powers of Vritra and Wagyl, and a offer to Ophis, dubbed Dragon Demonification by Mordred and Hans. The armor becomes colored in a mix of purple, silver, white and black and gains ten mechanical Dragon wings and several tentacles, similar to Vritra Transformation. This form can only be sustained for a short time that has yet to be revealed in detail.
 * Vritra Inferno Cannon:
 * Alchemist Deletion Field:
 * Vala Army:
 * Vritra Summoning: Lancelot gained the ability to summon Vritra into battle by performing a chant.
 * Lancelot: Be resurrected! Abyssal Prison Dragon that dwells inside of me!

Chants
Diabolus Dragon Beast: Lilith= Arthur, Brynhildr and Ophis alternate lines when chanting the (Pseudo)/[True] Diabolus Dragon Beast: Lilith chant.


 * Arthur: The Crimson Red Dragon Emperor and Strongest Valkyrie dwelling within me, awaken from your domains of dominance
 * Brynhildr: The Crimson Heavenly Dragon I possessed, rise up to become a King and roar a plaza of flames
 * Ophis: The jet-black Goddess of the Infinity
 * Brynhildr: The glorious Gods of Dreams and the Dreamtime
 * Brynhildr and Ophis: Watch over the (false)/[true] forbidden existence we shall become that transcends the boundaries
 * Both: Thou shall dance like radiance within our [perfected black] inferno!

Vali, Albion, and Ophis alternate lines when chanting the Diabolus Dragon Beast: Apollo chant.
 * -|Diabolus Dragon Beast: Phoebus=
 * Vali: The Pure-White Dragon Emperor dwelling within me, rise up from your supremacy
 * Albion: The silvery-white and bright-orange Suns I possess within me, claim the throne of the Dawn
 * Ophis: The jet-black Goddess of Infinity
 * Vali: The mysterious and unfathomable child of Greece
 * Vali and Albion: We shall transcend the limits to accept the oath
 * All: Thou shalt kneel down before our bright and glorious existence!

Lancelot, Vritra and Wagyl alternate lines when chanting the Diabolus Dragon Beast: Vritra chant.
 * -|Diabolus Dragon Beast: Vritra=
 * Lancelot: The Abyssal Dragon King and dwelling within me, awaken from your prison of sins
 * Vritra: The Prison Dragon King I possess within me, revamp your crown and claim the throne of the Dusk
 * Wagyl: The rainbow God of the Dreamtime
 * Lancelot: The essence of the knight of lake and his kindred
 * Vritra and Wagyl: Watch over our forbidden existences that eliminates the boundaries
 * Both: Thou shall scream in prey under our sacred existence!