As the battle between Cerberus and the RK-4 draws to an end, the 12th Elder arrives on the scene with Taze, the captain of Cerberus. Taze defeated Tao and Takeo on the way and carried them with her. She attacks Ked and Rodin for getting injured, then proceeds to attack Regis. She attacks M-21, when he interferes, before attacking Regis again and almost killing him. Regis is saved by the timely arrival of Seira, Rai, and Frankenstein. This leads to a short battle between Seira and Taze that ends in Taze's defeat, angering the Elder. He then proceeds to release his powerful aura and decides to take care of the enemy himself. Meanwhile, Frankenstein decides to take on the Elder to prevent Rai from having to use his powers again and also to find out something from him. He asks Rai to leave the rest to him and Rai releases the seal on Frankenstein's power.
Seeing Frankenstein come at the Elder, Rodin attacks him, only to be defeated instantaneously. Frankenstein taunts the Elder for letting his underlings fight and they both clash auras. Their clash of auras causes explosions. Their battle starts with words as Elder tauntingly asks Frankenstein who he thinks he is, only to be taunted back by Frankenstein asking if the other Elders know what he is doing. This infuriates the 12th Elder who attacks Frankenstein with an energy blast. Frankenstein easily dodges and they both clash fists. The 12th Elder tries to attack again but is stopped by multiple dark spears, which he easily destroys. But to his shock, there is a rain of dark projectiles coming at him from above. Elder calls Frankenstein's attacks petty tricks but Frankenstein keeps taunting him, infuriating him even more. They both clash multiple times but to no avail as they are able to dodge each other easily. After the initial clashes, the 12th Elder is the first to obtain injury. This shocks the Elder so he asks Frankenstein if Dr. Crombel created him, which Frankenstein says is an insult to him.
They clash again, then Frankenstein attacks Ked while pretending to attack the Elder, for which he offers a sarcastic "apology". The 12th Elder claims that he has had enough and decides to get serious. He transforms into a bat-like monster. Seeing his true form, Frankenstein is reassured that Roctis, who betrayed his master, has indeed formed a contract with the Elder and he gets excited now that he has an idea of his enemy's location. He then summons Dark Spear with a menacing smile on his face, causing Yonsu who was watching the battle to wonder if Frankenstein is the devil.
The battle continues and both opponents dodge each other's attacks. The Elder attacks with continuous blasts of energy which causes injuries to Frankenstein. Frankenstein retaliates with dark matter shaped like thin wires which cause an explosion and the Elder to take serious damage for the first time in the battle. The Elder crashes on the building roof, thus bringing him in Frankenstein's attack range. The Elder then uses his ability of flight to avoid Frankenstein, but Frankenstein attacks him with a huge amount of dark matter causing him to collapse on the roof again. Now crouched on the floor and injured all over, the Elder is in disbelief that he is losing to Frankenstein despite all the power he gained from Roctis. Frankenstein towers over him with a dark look on his face and taunts the Elder for the amount of power Roctis gave him. At that moment, Rai calls Frankenstein and tells him to calm him down.
Seeing that Frankenstein is listening to Rai, the 12th Elder quickly takes Rai hostage, much to the disbelief of others. He tries to use the time to recover his injuries and escape from there, but in arrogance threatens to kill all KSA agents, which angers Rai. This leads to Rai facing the 12th Elder himself.