In a space far larger than any of the previous rooms, Lafei's rising flames of demonic power churned the air into chaotic currents, blasting outward and sweeping across Leo, Rias, and Sona Sitri.
Leo remained steady, but Rias and Sona's expressions hardened. Instinctively, they released their own demonic power—red flames and blue flames rising around them—to push back against Lafei's aura.
Lafei's anger slowly faded from his face, replaced by a cold, mocking smile.
"You didn't actually think I set up all those rooms because I was scared of your strength… did you?"
His tone dripped with ridicule.
"Ridiculous. Why would I fear a few newborn devils like you?"
"The maze, the traps, the monsters—those were just precautions. A way to prevent accidents…"
"And a chance to test the things those people lent to me."
"Those traps, creatures, even the magicians who came with us—all of it was provided by individuals far removed from our True Maou Faction. I agreed to help them test their creations, so they lent them to me."
As he spoke, the flames around him grew larger, more violent—far more dangerous.
Then he said a sentence that changed the atmosphere completely.
"I never intended to rely on those toys to kill you. Only I—or rather, we, the True Maou Faction—have the power to kill you."
The moment that declaration fell, familiar light from magic circles filled the room. Silhouettes appeared one after another.
They spread their devil wings—some with a pair, some with two pairs, and a few with three pairs. Their demonic power surged accordingly. Some were Low-Class Devil level, some Mid-Class Devil, and the ones with six wings were naturally High-Class Devil strength.
"Attack!"
With a swing of Lafei's hand, the devils around him took to the air and unleashed volleys of demonic power blasts.
"Boom! Boom! Boom! Boom! Boom!"
A storm of magic bullets rained down like artillery shells, covering Leo's group completely. Explosions stacked atop explosions, turning the air into a violent mix of heat and shockwaves that ravaged the entire room.
The bombardment didn't stop. More blasts poured into the inferno, detonating endlessly and shaking the ground.
A combined attack like this could turn any High-Class Devil into dust—leaving nothing behind.
But Leo's group survived.
In the center of the explosions, the three stood back-to-back, forming a triangle. Each extended both hands forward, releasing demonic power to construct defensive magic circles, holding back the onslaught and keeping the explosions outside their barrier.
"Nh…!"
Rias and Sona struggled, stifling pained groans, but they held on.
Lafei watched, expression twisting with wicked amusement.
"As expected of the newborn devils favored by those false Maou. Your demonic power is at least somewhat impressive."
"But it's a pity. You're too young. You won't live long enough to grow."
Lafei raised his hand as well, gathering demonic power—far more than the others. His magic bullet grew enormous, half the size of his own body, hot enough to vaporize the air around it.
He fired.
"Die!"
"Not good!"
Rias and Sona's hearts lurched.
A full-power strike from an Ultimate-Class Devil—none of them could withstand that alone.
If the three of them combined their defenses, maybe. But right now they were forced to stand back-to-back, each defending one direction. Only one of them would take Lafei's hit directly.
And that person was—
The one with the weakest demonic power.
Sona Sitri.
"Sona!!"
Rias shouted.
Sona didn't answer. She simply gritted her teeth, eyes filled with resolve. She prepared to pour every last drop of demonic power into her defense—
Until Leo's voice cut through the chaos.
"Switch!"
Before she even thought, Sona obeyed instinctively. She shifted her position with Leo, trading places in a swift, practiced movement.
Leo now faced Lafei's attack.
"BOOOOOM!!!"
The massive blast smashed into Leo's defensive magic circle, generating the loudest explosion yet. Flames and shockwaves swept across the entire chamber, blowing back every Old Maou Faction devil.
Smoke billowed thickly.
But when it cleared—
Leo was still standing tall.
His defensive magic circle hadn't cracked. Not even once.
"What?"
The Old Maou devils froze.
"No… way!"
Lafei's smile turned rigid.
Rias and Sona stared wide-eyed at Leo's calm expression.
"This…"
Words failed them.
But Leo had no intention of stopping.
"Now!"
He flipped his magic circle—shifting it from defense to offense. The shield became a cannon.
Dozens of high-power demonic blasts erupted outward, raining toward the surrounding enemies.
"Turn to ash!"
"Disappear!"
Snapped back to reality by Leo's shout, Rias and Sona reversed their own magic circles as well, unleashing a storm of magic bullets in every direction.
"Boom! Boom! Boom! Boom! Boom—!"
Explosions rocked the battlefield again, but this time they engulfed only the Old Maou devils.
Several never even reacted before the blasts hit them—screams echoed as bodies burned to charcoal or disintegrated entirely. Only a few High-Class Devils and a handful of Mid-Class Devils survived the barrage.
"Bastard!"
Lafei roared.
He surged with rage, forming another massive magic bullet—then fired it straight at Leo.
"BOOOOOM!!!"
Once again, Leo shifted his magic circle into a shield, blocking the attack in a fierce clash of demonic power and pressure.
And once again…
Lafei's attack failed to break through.
"No! Impossible! IMPOSSIBLE!"
Lafei screamed, firing again and again—each magic bullet larger than the last, eventually matching his own size. His power rose with every shot, fury making him reckless.
Leo, unfazed, calmly expanded his own magic circle, reinforcing it while continuing to block every attack. His demonic power output rose steadily, rising… rising…
Until—
His aura surged upward like a blazing inferno.
Equal to Lafei's.
An Ultimate-Class Devil's power.
Leo had reached it.
"No… no… this can't be…!"
Lafei's eyes went wide, trembling with disbelief.
Rias and Sona were just as stunned.
"Ultimate-Class Devil…" Rias whispered.
"So he really did reach a higher realm…" Sona murmured, her heartbeat stumbling.
Leo, however, showed no change in expression.
He flipped his magic circle again—turning the shield back into a cannon.
"Run!!"
"Get away!!"
The remaining Old Maou devils panicked instantly, flapping their devil wings desperately to flee.
"You won't!"
Lafei snapped out of his shock, unleashing all eight of his devil wings and shooting toward Leo.
Seeing this, Leo didn't hesitate. He aimed the cannon at Lafei directly and fired.
The blasts he unleashed were on par with Lafei's earlier attacks—each one half his size at minimum, some as large as his entire body. Sonic booms cracked the air, the sheer force undeniable.
Lafei, of course, wasn't outmatched in technique. He deployed a defensive magic circle while charging forward, pushing through the exploding blasts.
"Whoosh!"
Leo spread his devil wings as well—four pairs, eight wings—soaring upward to meet him.
That sight struck every onlooker to the core.
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Extra chapter!
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You can read up to chapter 143 on patreon.com/NiaXD.