Vali and Azazel watched the Devils as they approach the schoolyard. They were understandably shocked when they say Valper's intent to combine all the stolen Excalibur swords. On the other hand, Kokabiel is very disappointed that either Sirzechs or Serafall didn't arrive and destroyed the whole gymnasium in a single attack in a fit of fury. Nevertheless, Kokabiel calmed down as they probably called for reinforcements and he might as well amuse himself as he waits for their arrival.
With a single snap of his fingers, Kokabiel summoned multiple beasts, the Cerberus, which is only suppose to be in the Hades' domain.
"...Are those real?" Vali asked Azazel.
"Most likely not as they are too weak... But how did Kokabiel get his hands on these things? Looks like the situation is more complicated than I thought." Azazel replied with a furrowed brows.
Rias and her peerage followed Aika's advice on prolonging the battle as much as possible but what they are doing is too obvious for trained and experienced eyes. They instantly guessed their goal but Kokabiel didn't do anything about it as it is amusing at its own right. Kokabiel also took notice of Aika with her 'very normal' aura of a Human and her Sacred Gear but disregarded her immediately after seeing what she's holding, the Aeternam Somnium. It's the last Sacred Gear that the Biblical God created and it acts like a Longinus by only having one host each generation despite its very lackluster abilities like enhancing the physical attributes of the possessor and returning to the owner when thrown. The only mysterious 'ability' it has is the fact that the possessor would always get dragged to the supernatural world before it can even awaken.
Azazel, however, has a different opinion as he has a clue on what's the true capability of that Sacred Gear, "Albion... Are you sure that Sacred Gear is 'dead'?"
"Yes," Albion answered him briefly.
"...Impossible. Aeternam Somnium's spirit could never die." Azazel asserted.
"Hmm? Aeternam Somnium? That 'fake' Longinus?" Vali was a bit surprised at Azazel's words.
"Vali... You can never call that Sacred Gear as fake Longinus."
"Why? Because it's strong? But from all the records of its possessor, there had never been one that manages to step on the ranks of even Middle-Class Devil."
"It's not because it is strong... It's because it just shows how much technical skills God has in his arsenal. And I doubt anyone could control and tap into that Sacred Gear's potential which is comparable to True Longinus." Azazel ended his words there, 'And father's greatest masterpiece before his fall.'
"And what sort of creature resides in that, that you said it could never die. Something like that must be on the level of two Heavenly Dragons."
"I can't tell you that yet. And I doubt that information would be useful at all. If Albion is saying that the Sacred Gear is 'dead' then some changes might have happened in its inner workings. The spirits might have even escaped or were claimed back."
"Spirits? There are more than one? Escape? That's impossible as even the Heavenly Dragons can't do so. And claimed back? What?" Vali became even more confused at her nonsensical words.
"That's why I said you don't need to know yet." Azazel chuckled but deep inside, he's planning on how he should contact the girl in question.
Vali knew that he wouldn't be able to get more information from Azazel and just focused on the ongoing 'childish' fight. He would put more attention to Issei and Aika than the rest.
As they are fighting the fire-breathing, triple-headed beast, supports came in as Xenovia and Yuuto made their appearance and killed one Cerberus each.
But just as they are 'playing' around with the Cerberus, Valper finished fusing the four Excalibur swords and the residual magic from the ceremony is threatening to explode within just 10 minutes and it would affect the whole town if that were to happen.
Aika already tried assassinating Valper before he could even finish fusing the swords, but Kokabiel put up a barrier around the ceremony making it impossible for her to even approach him. Aika thought of using the 'candy' Kisuke gave her some time ago but immediately discarded that idea as the real enemy here is Kokabiel, and that 'candy' of her would probably only give her a limited amount of time and she'll be retired after that.
The barrier hasn't disappeared even now so all of them can't do anything about the ceremony circle continuing to gather mana from the surrounding. They had no choice but kill the remaining Cerberus' and deal with Kokabiel. Aika has the same idea as a living flesh is easier to pierce than a hard barrier. The problem is, it would be an aerial battle and she only has one chance.
Freed then came out to control the fused Excalibur. Valper then revealed the real goal of the experiment where Yuuto is part of. By extracting the essence necessary to control the Excalibur, Valper was able to create an artificial user. He even tossed a crystal of this extracted essence to the disgruntled Yuuto to mock him.
To everyone's shock, however, Yuuto managed to fuse with it, and his Sacred Gear, Sword Birth, achieved an irregular Balance Breaker where opposing forces were fused into one sword, 'Sword of Betrayer' as he called it.
Yuuto was able to fight Freed evenly with his Excalibur which gave Valper another shock. Xenovia, however, won't stay silent and revealed her own trump card, the Durandal. Xenovia is a natural Holy Sword wielder and against the incomplete Excalibur, Durandal easily destroyed it. Using this chance, Yuuto gave Freed a large wound across his chest, taking him out of the battle.
Valper was cornered and an idea came to him, but before he could say it out loud, Kokabiel killed him.
Kokabiel slowly flew down, "You were a great man, Valper. It's beyond impressive that you were able to figure it out in the end. But I should have eliminated you from the start and forged ahead alone." Kokabiel then looked towards the tired Devils, "Now then, let's end this. Go ahead and transfer the Red Dragon Emperor's power to someone. Hurry it up!"
Issei glared at him and looked towards his master, "Buchou! I'm ready!" Issei knew that out of all them, Rias has the most destructive power. He knew the difference in power and didn't hesitate to call out to her for the transfer.
After the transfer, Rias' Demonic Power shoots up multiple times, impressing even Kokabiel, "Hahaha! Good, good! Your power is almost as strong as the Devil King's! You and your brother have truly been blessed with nigh unbelievable abilities!
Rias' conjured the most destructive attack she can in the form of a gigantic ball of Power of Destruction, "VANISH!"
Kokabiel laughed out loud and intended to take it head-on, "What fun you are, sister of Devil King Sirzechs!" The power of destruction crashed onto him, "NNNGH!" And he's enjoying the sensation.
Akeno took this chance to get behind him and attacked with her lightning, "Hooh... You must be Baraqiel's..."
Without letting him finish, Akeno increased the intensity of her attack, "Don't you dare speak of him and me in the same breath!!!"
Kokabiel already had enough and crushed both of the magic with his bare hands.
"It can't be..." Rias couldn't believe that she can't even wound him despite all of that magic. She and her peerage sorely underestimated him, "All that magic power still wasn't enough to beat him..."
Aika clicked her tongue at what just happened. She already expected that Kokabiel won't be defeated with just Rias' attack, but she didn't expect that Akeno would also attack him from behind making her lose her chance to stab him at the back, 'I'm really too inexperienced for this...'