Diabolos Dragon

Diabolos Dragon is the second upgraded form of the Scale Mail after Issei and Vali borrow the power of Ophis.

Summary
The Diabolos Dragon is first seen in Volume 20 when Issei unlocked that form with Ophis' help, to overcome Rizevim and his Sacred Gear Canceller. Due to the power of the form, Issei immediately collapsed after its usage where all of his organs stopped functioning except for his heart. This issue was later solved after Ophis reduced the power of the Diabolos Dragon to prevent such a huge setback.

Vali also attains his own version of the Diabolos Dragon in Volume 21 with Ophis' assistance.

Diabolos Dragon God
Diabolos Dragon・G is Issei's version of the Diabolos Dragon. The armor gains a mix of crimson and black, along with a second set of Dragon wings totalling four. After the battle against Apophis, Ophis adjusts the DxD G, removing the infinity in it, being dubbed Pseudo-Dragon Defication. The form can only be maintained for three minutes.


 * Infinity Blaster: A further enhanced version of the Crimson Blaster, the wings contain cannons that shoot out a powerful blast of red and black aura that leaves even Rizevim injured to a extent that his body is almost fatally damaged.


 * Longinus Smasher: This 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 and can also be used in tandem with the Infinity Blaster.

Diabolos Dragon Lucifer
Diabolos Dragon・L is Vali's version of the Diabolos Dragon. The armor gains a mix of silver and black, while Vali obtains 12 Devil wings. The form can only be maintained for three minutes.


 * Satan Compression Divider: Vali releases a burst of Slivery-white and jet-black streams of demonic radiance that instantly compress anything caught in it over and over again, until eventually eliminated.


 * Satan Lucifer Smasher: An enhanced version of the Longinus Smasher, the armor opens out from the abdomen and fires a massive bombardment of sliver-white and jet-black aura.

Chants
Issei and Ophis alternate lines when chanting the Diabolos Dragon God chant.


 * Issei: I, The Crimson Red Dragon dwelling within me, awaken from your dominance 
 * Ddraig: The Crimson Heavenly Dragon I possess within me, rise up to become a King
 * Ophis: The jet-black God of Infinity
 * Issei: The glorious Red God of Dreams
 * Issei and Ddraig: Watch over the forbidden existence we shall become that transcends the boundaries
 * All: We shall dance like radiance within the inferno

Vali, Albion, and Ophis alternate lines when chanting the Diabolos Dragon Lucifer chant.


 * Vali: The pure White Dragon dwelling within me, rise up from your supremacy
 * Albion: The silvery-white Morning Star I possess within me, claim the throne of Dawn
 * Ophis: The jet-black God of Infinity
 * Vali: The mysterious and unfathomable father of Devils
 * Vali and Albion: We shall transcend the limits to accept the oath
 * All: Thou shalt kneel down before our bright and glorious existence!