As a result of his comprehending the principles behind mana zone, mana method, ultimate magic, as well as his experience in shifting between magic attributes via his [Demon Slaying Magic] and switching the nature of his mana through his human and elven state, Grim had gained an insight into magic like no other before him.
Compared to a genius like Asta who managed to achieve [Devil Union] in a matter of days, Grim took his time conceptualising, creating and forming the [0th Form]. Since this was not mana zone, mana method, ultimate magic or even devil union, he had no one to guide him. This was a path completely unique to him. One he had to pave himself.
Inside the independant space known as [Glamour World], under the constant threat of death and replacement from his highly aggressive clones, there were only two outcomes. Live or Die.
Pushed to both his physical and mental limits time and time again, his body entered an extreme state of fight or flight. Losing himself to the endless slaughter, the time he spent inside [Glamour World] felt like it lasted an age. Covered in blood and spending his days fighting and devouring clones, he improved at a rate that far surpassed what other mages were capable of. Becoming so strong that even [Glamour World] threatened to break with the mere flex of his power. But it wasn't enough. He wanted more. And then one day he finally did it. He evolved.
***
As soon as he took a step forward, every mage and devil alike felt a shift in the air. Even Lucifero, the king of all devils whose body brimmed with overwhelming magic power felt somewhat tense.
For all of them, Grim included, this was an unprecedented moment. Having never used the [0th Form] in fear of destroying [Glamour World] and ending his training early, this was the first time he had properly felt what this form was capable of.
With the [Demon Slayer Mark] resting on both sides of his cheeks, he knew that he had done something irreversible.
An earthquake rattled the kingdom. The sound of innocents and the roar of mana itself echoed through the air.
'This pressure... What is this?'
It felt as if the world was trying the claw itself apart.
"What do you feel?"
"Strength? Emotion? Heart? Anger? Need? Emptiness? Completion?"
"Hunger."
Deep within the mindscape, King smiled.
"Then go feast."
"Hrrrghh!!!"
Taking a step forward, the ground beneath his feet quaked and shattered as everyone, be they human or devil felt a shift in the air. Even Lucifero, the mighty king of all devils and ruler of gravity felt a sense of unease well up in his heart as Grim blitzed past him and the two of them stood back to back.
'He's behind me!'
Clenching his fist and locking space with his gravity, the king of devils span around and threw a punch. Without hesitation or the use of his gravity magic, just by relying on his physical body alone he raised his hand and punched out with a momentum that seemed unstoppable.
Staring at the oncoming fist, Grim revealed a full set of 64 teeth (double the normal amount) and matched the devil king's arrogance by clenching his hand into a fist and striking out with no intention of retreating or dodging.
Lucifero's eyes widened at the manoeuvre.
""GRIM DON'T!!""
The now conscious Asta and the other Clover Kingdom fighters cried out seeing his actions.
*BOOOM!!*
With a loud bang, the two fists collided.
Just as everyone thought that Grim would definitely lose, some even choosing to turn their heads away. A deep growl rumbled out of his body as the two clashed.
"Nrghhh!!"
"Urggghhh!!"
A powerful shockwave spread out causing spiderweb like cracks to appear on the floor as the spectators were forced to cover their faces. Even from this distance, the might of their collision could have ended them.
Pushed several feet back by the aftermath, the force generated was enough to tear the sleeve on Grim's arm. But he managed to stop himself from going any further and regain his balance.
"What?!"
The feral Lucifero revealed a surprised expression.
"An insignificant human actually withstood a punch from me?"
Contrary to the previous times he had fought Grim, this was the first time he had taken a direct punch from him without suffering.
"Pahahahahahahahahahahahahaha!!"
Putting his hands up again and laughing like a maniac, Grim's mana surged as he took up another stance and launched himself at the devil king.
Everyone looked at his actions shocked. After all, not too long ago the combined efforts of him and Yami could barely even damage the restless king and now here he was was charging at him with his fist raised!
And then...
*SWOOSH!!*
-KAWAAAAAAAAAAAAANG!!
Grim slipped past Lucifero's jab and struck him dead centre in the middle of his face.
Carrying enough force behind him, Lucifero actually toppled over as Grim's fist drove the back of his head straight into the ground.
"This... can't be."
"What just happened?!"
'This boy... He's overwhelming Lucifero.'
Even if his state was incomplete and part of his mind had returned, there was no being, devil or otherwise that should be capable of doing what that boy just did to a feral Lucifero... It was inconceivable.
Narrowing his eyes, the look in Adramelch's eyes changed when he looked at Grim.
Where Lucifero's head smashed into the ground, an indented and cracked patch marked the spot.
"Hoo." Grim grinned feeling a tingling sensation ripple on the surface of his skin.
"HAAAAAAARGHHHHHHHHHHHH!!!"
Lucifero suddenly exploded with rage!
Compressing all the gravity magic around him and unleashing it all at once, a laughing Grim was forced to retreat as Lucifero's gravity razed the area.
"How Dare YOU!!" He spoke. His body floating up off the ground.
"To put your hands on me!"
*CRACK!!*
"TO MAKE ME BLEED!!"
*CRACK* *CRACK!!*
"YOU DESERVE PAIN! DEATH! AND TORMENT!!!"
*CRACK!!* *CRACK!!* *CRACK!!*
Breaking the earth apart and raising them high into the air. He used [Gravity Magic: Evil God's Pressure Craft] to shape them into the form of hundreds of arrows.
"Heh." Grim grinned showing off his canines.
"DIEEE!!" Thrusting his arm foward, he let loose a shower of arrows upon the grinning Grim.
Summoning out a single beast sword, in the face of such an attack Grim swung his sword with such force and vigor that he space apart and let the arrows fill it.
'WHAT!' In alarm, both Finral and Langris almost stood up at the same time.
What Grim had done wasn't spatial magic, but it defintely had the same principles. Of course it wasn't like spatial magic was the only type of magic that could manipulate space. Lucifero's teleportation was a clear example of that. But Grim... He wasn't Lucifero.
Dissipating the sword, Grim extended the chain wrapped around arm and hooked it around Lucifero's ankle. Then with a simple yank, he pulled down the O' so mighty king of devils and charged at him. But before his fist could connect, Lucifero used his gravity magic to warp space and teleport behind him. Now that he wasn't using his Kitsune/Nogitsune powers, there was no way for him to avoid this blow.
With this simple gravity enhanced punch, his spine would break like glass... At least that what should have happened.
-BOOM!!
Landing his punch, the air rippled. Having achieved a successful attack, the malicious smile on Lucifero's grew only to falter at the last minute. Feeling Grim's skin shiver and wriggle under his fist, an indescribable expression made its way onto his face.
This sensation... He had felt it when his and Grim's fists had collided earlier.
Just like back then, the physical strnegth behind his punch should have shattered his entire arm. But for some reason it was fine.
!!!
Feeling like something was terribly wrong, he prepare to warp-
"Ah, ah, ah." A wicked sounding laughter echoed in his ears.
*FWOOM!!*
Suddenly, all the gravity magic around them vanished. No! Grim pulled it into himself.
'T-This... WHAT IS THIS!'
Similar to the way he locked space in order to trap Grim in one area, Grim had done something to the surrounding space and trapped Lucifero.
Moments later, the space around Grim's body seemed to twist and collapse in on itself causing him to vanish only to reappear behind Lucifero in a manner that copied what the devil king had done to him moments earlier.
'TELEPORTATION!'
***
In the distance, the clover knights watched the battle with varried expressions. Some were happy, others concerned.
"Hey." Asta spoke up finally healed from his previous injuries. "I know that I might be a bit dumb when it comes to magic, but does anyone else not understand what is going on?"
-Silence
Seeing that no one was answering, hesitantly Finral decided to voice his thoughts.
From him tearing space apart, stopping Lucifero from manipulating space to teleport away and now using a mysterious method to grant him the ability of teleportation, it was clear that Grim's understanding of spatial magic was dangerously high.
Tearing/ Gouging space - A Langris specialty.
Stopping teleportation - An ability Wizard King Jester used to block spatial magic inside his barriers.
Self teleportation - On the level of the instant teleportation spell he created through mana method.
"Grim... I think he's replicating spatial mage abilities by devouring the space around him."
Devouring space? Was such a thing possible?
"Its more than that." Secre suddenly spoke up surprising everyone.
"Everytime he hit Lucifero or Lucifero hit him, his skin seems to ripple."
"So?" Asta questioned not understanding where she was going with this.
"My magic allows me seal away the damage someone receives... I think Grim is doing something similar... I think he's devouring his own damage."
"What!" Everyone gasped unable to hide their surprise.
"I don't know how he's doing it, but right now, Grim is invincible."