Cataclysm // Demon Slayer Deku

Devastation

"Demon Breathing: Tenth Form: Inferno Lash!" 

Hashibira-San, The Demon Hashira, whipped his chain-like weapon around at incredible speeds, the length of the chain glowing a bright red with a searing heat felt by everyone. The scorching hot chain wrapped around the demon king's body, holding him in place as his very flesh began to melt.

"Blood Breathing: Second Form: Warfare!"

 Gyutaro-San, The Blood Hashira, sent out outwardly expanding slashes combined with his blood projectiles, each one undoubtedly fused with wisteria poison.

"Steel Breathing: First Form: Piston Strike!"

 Takeshi, The Steel Hashira, moved his gauntlet-cladded fists forward at incredible speeds, disrupting the flow of wind as his fist struck the demon king square in the face, the force of the punch sending him flying back, crashing into a nearby tree. At the same time, Gyutaro's blood projectiles struck the demon king, leaving small cuts along his body before they quickly faded away.

"Death Breathing: Eighth Form: Withering Blade!"

 Gushiken, The Death Hashira, reached behind his back, grabbing onto both of his scythes, the cloth that wrapped around them instantly withered and fell apart. He dashed forward, an unreadable expression on his face as he struck the demon king's legs before he could recover, only move behind the demon and slice straight through his chest.

"Time Breathing: Ninth Form: Clockworks!"

 An intense amount of wind spun around the Time Hashira's body, her longsword spinning around intensely, striking each of the demon king's limbs, preventing him from counter attacking.

"Star Breathing: Eleventh Form: Constellation!"

 The Star Hashira performed countless, swift thrust attacks, each one creating a concentrated force upon each contact points.

The demon king's face began to twitch in what could only be described as fury, an intense buildup of flames shooting out from his body. However, Genki continued forward.

"Jester Breathing: Fourth Form: Domino Fall!" 

Genki swiftly clicked through the demon king's attack, only to slide between his legs, slamming his glaive into the demon king's back, forcing him forward in a zigzag pattern as he continued to attack, leading the Tanjiro Kamado in the middle of us all.

"Thunder Breathing: Seventh Form: Flaming Thunder God!"

I dashed forward, unleashing a singular forward slash at a low stance. I met the demon king's observant gaze with my own, crashing my blade through the demon king's chest with as much strength as I could muster, knocking him back slightly.

I gridded my teeth together as I was knocked back a couple of meters by a flame projectile, the heat of which far surpassed father's. It wasn't even a comparison.

I was barely even able to defeat him... even with all of the Hashira, can we really win? If sunlight doesn't effect the demon king then that would make nichirin weapons pointless as well.

The best we can do is force him to retreat.

But how will we even manage that? He hasn't shown his true strength yet, that much is obvious.

But...

All of us, once again, leaped forward to attack all at once. "If we just keep attacking, he won't have time to counter," I thought to myself, tightening my grip on my katana.

The demon king got into a low stance, katana raised above his head as it ignited, fully wrapped in flames.

"Sun Breathing: Second Form: Clear Blue Sky!"