Eren gulped down a vial of an expensive mana recovery potion as he looked at Oliver's team with his deep blue eyes. His otherworldly nature couldn't be masked when he was in this form.

Eren used the potion because he needed to refill his mana reserves. His tank spell took a huge toll on his mana reserves after all.

The ground quaked and the V-section of the ground that was cut by the elemental sword was lifted. A threatening amount of mana pulse was released as Eren finished casting his brand-new spell with exceptional skill as if he had been casting it for a very long time.

Behemoth!

Oliver sensed a threatening presence under Eren's feet. He didn't know how a close combat expert could cast a spell like this. But this was not the time to ask anyone.

He wanted to attack Eren right then and there before he finished casting the spell. Suddenly, he was subjected to the butcher's unleashed soul sense.

Oliver was sucked into the illusion of a gory world once again. This time he was a bit prepared and partially convinced himself that the illusion he was seeing was not real. But his soul was affected by Eren's soul sense nonetheless. As a result, the elemental sword halted in midair and couldn't finish attacking Eren and Kirin.

Eren used his soul sense plus Sedating Gaze to disrupt the enemy's plan of stopping him from using Behemoth. Doing this, he gained enough time to finish the spell.

An earth-element creature was summoned into existence by Eren's spell. It had a lizard-like face with a bird-like beak. The creature also had exoskeleton fangs near his half-open mouth.

The creature had a relatively short horn for its nose. A series of horns also peeked through its forehead and other parts of its face. The beast had spikes on its back that extended over its tail.

His entire body was made of earth. Light green, beast-like callous skin covered its entire body. The beastly skin made the Behemoth look even more intimidating.

Since Eren had summoned a D-Rank Behemoth, it was relatively smaller in size and less intimidating than what Gilhause had summoned for himself. Still, the beast's size was just right to tackle the large elemental sword with. And since its body was made from earth-element, it served as the perfect counter to a sword's attacks.

The beast stood on four giant, pillar-like legs. He had green eyes that shined brightly from time to time. And he also developed white spots all over his body.

Eren was now seen standing on the beast's head. Kirin stood just behind him. The butcher enjoyed seeing an elevated view of the surroundings from the beast's head. He felt as if he had a walking mini mountain under his feet that was ready to bend to his will.

'He he wasn't dueling with me seriously.'

Ivor gulped as he looked at Eren from a distance. He was already too stunned to do anything after seeing Argo's fierceness. He thought that that was probably going to be the shock of the day for him. But Eren's new spell turned him wrong.

He also wondered why Eren felt like he had been turned into a completely different person. He wasn't used to seeing him with white hair and blue eyes. Ivor couldn't fathom the butcher shifting between classes on a whim.

"Don't think too much or get greedy for power. He is unique. You are better off staying as a close combat expert for now."

Layla popped Ivor's bubble of having multiple classes. The latter also didn't know when he wanted to be more like Eren. He was astonished by Argo first and then by Eren once again.

Layla looked at Argo intently before saying a few things under her breath. She knew that Eliza would try to help Eren on his path so he could play an active role in the Lazarus project. But she was also sure that her Master wouldn't offer Eren too many benefits as well.

The demon beast egg given to Eren by Eliza was supposed to be an epic-tier beast. But Argo's mana signatures made her think otherwise.

Layla felt that Argo's signature wasn't the usual one of an epic-tier beast. They rivaled the power of dragons and beyond. And this was when the demon beast hadn't even learned to shapeshift into humanoid form and harness his individuality.

'Too many too many variables.'

Argo's incredibleness didn't really threaten the Lazarus project. But the homunculus thought that she should be careful nonetheless. Argo alone was the biggest anomaly Eren had under his banner.'

Layla thought to herself. She then looked at Eren himself before having another thought.

'We always knew he was going to get stronger with time, thanks to his bloodline. But this... is incomprehensible. How was he not apprehended by the forces of Anfang with his staggering progress? I need to consult with Master Eliza see what she has to say.'

Oliver could see Eren looking at him casually while enjoying his smoke. The butcher was waiting for Oliver to attack him this time with his elemental sword.

The Hound looked at Eren grimly and added.

"I won't ask when and how you obtained these myriad powers. Because I know you won't tell me. I won't ask you about your past as Osan Woods' Butcher because it doesn't matter anymore.

However, I do want to ask you something very pertinent. And I'd appreciate it if you could answer me. What is your role in matters related to Purgatory?"

According to Oliver, Eren or the Osan Woods' Butcher should not have sided with Layla. Because he had no reason to. And there was no sign of him using the artificial demon beast as well. As much as Oliver was intimidated by Argo, he knew that he was not the artificial demon beast that they had created inside the lab.

Arthur knew bits and pieces about what kind of powers Reen would have. And although Argo's Devour Ability paid homage to the artificial demon beast's powers, he was nothing like Reen.