Reborn in black clover with Demon Slaying magic

"No No NO!" Jumping in front of Grim, Luck blocked his way. "You got to fight that smoke guy earlier and you've already beat this guy before! Its my turn to have some fun!"

"What? When I beat this guy he was only using crystal magic. You're not seriously asking me to give you an opponent who uses two different types of magics are you?"

"Yes!"

"I refuse. And besides, that guy's looking right at me."

Seeing that Grim and Luck were too busy arguing instead of fighting, Asta took it upon himself to deal with the enemy.

"He's mine!!"

Charging forward with his giant sword, Asta prepared to end this fight as quickly as possible.

Seeing the orange glow on Grim's body and feeling the heat radiating off of him, an intense hatred spread through Mars's heart as he remembered the experiments he had to endure and the people he lost all in order to achieve his current power. But looking at someone like Grim who had an immense amount of mana and was capable of using secondary fire magic without having to go through the same things that he and his comrades had to go through caused a deep seated rage to bubble to the surface.

'Grim's already taken care of this guy before using only his beast swords as a weapon. If that's the case then there shouldn't be a problem taking this guy down with my anti-magic sword.'

Rushing forward with gusto, Asta readied his sword as he closed in on Mars's hulking figure.

Feeling the intense flames of hatred in heart spreading, Mars's entire body shook as his mana suddenly started to surge and create clusters of crystals all around him. Without taking his eyes off of Grim's figure, Mars created several harpe shaped blades that spun at a high speed before firing them off at the approaching Asta.

"ASTA!!" Noelle suddenly screamed.

*BANG!!*

*BANG!!*

*BANG!!*

'So fast!'

Furiously slashing at the sword projectiles, the weight of his giant sword slowed him down as it took to much time to swing while he was being attacked by the high speed swords.

'Dammit! I won't be able to keep up at this rate!'

*BANG!!*

And just like he said, he wasn't capable of keeping up the with speed of the attacks as he was eventually blown back and sent hurtling into the wall that Nero had previously been dragging him towards.

"ASTA!!" Gritting her teeth, Noelle pointed her wand at Mars and prepared a spell.

'I don't know what those flames of his do, but I'm sure it'd be for the best if I use my water magic to put them out.'

Feeling her mana gathering, an enraged Mars charged towards her and used the moment she was defenseless to swipe at her.

"ThE WeAK HaVE NO PlaCe on tHe BaTtlEfiElD!!"

"NOELLE!!" Mimosa screamed after watching her cousin get flung across the room like a ragdoll. Running to her side she saw a nasty wound on her stomach.

Hearing her scream, both Grim and Luck stopped arguing and finally saw what was going on.

"Noelle..." Seeing his teammate lying on the floor with blood spurting out from a wound, the previous smiling Grim stopped laughing. While his relationship with Noelle wasn't exactly the best, the sight of a teammate approaching death's door caused something in his soul to shudder. He didn't know if it was from a past experience or not, but this feeling... He didn't like it.

"Um Grim..." Feeling a weird change in Grim's attitude, Luck instinctively moved aside as Grim's mana started to grow and heat the surrounding area.

Feeling the sudden rise of temperature in the room, Klaus and Yuno who were both trapped inside crystals looked towards Grim who was walking towards Mars.

With every step he took, the temperature rose higher and higher to the point that even Mimosa's plants on her Princess Healing Flower Robe's were being affected and drying out.

"Grim..."

---

-Elsewhere-

'This mana... Its that kid again...'

Feeling Grim's mana, Lotus looked in the direction it was coming from and realized it was the area that Mars was supposed to be investigating.

---

"Heheheh, its really funny." Grim's laughing voice echoed across the room as he closed in on the enraged Mars who was also being affected by the heat. "I don't even know why I'm feeling this way right now... but this feeling inside of me... its really unpleasant." While speaking, his grimoire floated up besides him and stared glowing bright orange as new words started appearing on the Breath of Flames page.

"Lets forget about what I said earlier in regards to me breaking your ribs okay. Because right now, I REALLY, REALLY WANT TO BREAK YOU."

Materializing his flame sword into his right hand, all the previous heat he released into the air started gathering onto him and his sword as he took up a new stance.

Blinded by his past memories and hatred of Grim's abilities, Mars suddenly roared and created another giant crystal sword.

[Crystal Creation Magic: Laevateinn]

[Breath of Flame- 1st Form: Unknowing Fire]

Crossing the space between them in nearly an instant, Grim left a trail of fire in his wake as he suddenly appeared behind Mars with his back to him.

"Earlier you said that the weak have no place on the field of battle right?"

Feeling an intense heat spreading from inside his crystal armour, Mars started looking around confused as he no idea how Grim had gotten behind him or why he was suddenly feeling hot.

"Since you think that way... Do me a favor and get off my battlefield."

Feeling the temperature inside his armour rise again, Mars's eyes went wide as bright orange light burst through the cracks in his armour.

*BOOM!!*

Watching the crystal armour suddenly explode, looks of shock and awe swept across the faces of the Clover Kingdom mages. Even the injured Noelle couldn't hide her surprise as she saw Grim standing in the sea of fire surrounded by broken crystals.

"Amazing..." Yuno mumbled before tightening his fists.

Being at the epicentre of the explosion, Mars's body now covered in burns was sent hurtling away.

*RUMBLE* *RUMBLE*

Feeling the ground shake, Grim and the rest of his companions watched as parts of the ceiling started to fall.

"The dungeon's collapsing!!" Klaus yelled. After being knocked unconscious by the explosion, Mars's crystal had weakened by a considerable amount allowing him and Yuno to break out of their bindings.

"We have to go!"

"Wait! Where's Asta?" Someone suddenly asked after not seeing him.

"I'm right here!" Bursting out from a destroyed wall and carrying an unfamiliar black sword with him, Asta appeared before everyone else.

"Yuno!" Klaus shouted.

"I'm on it!"

[Wind Creation Magic: Heavenly Wind Ark]

Manifesting a large gust of wind under their feet, Yuno brought everyone away from the crumbling area.

"Wait!" Grim suddenly shouted. "What about the treasure!"

"If we stay we'll be burried along with it!" Klaus yelled over the sound of the area collapsing.

"Tch." Gritting his teeth, Grim looked away from the pile of riches and focused his attention on Asta's new sword.

---

As the Clover mages were escaping, a hidden Lotus deactivated his ace magic spell Hermit's thick smoke, a spell that had the ability to make its user transparent.

"Well then." He walked over towards Mars and the treasures. "Lets get you out of here."