For the next hour, Leo and the others passed through three more trials.
The first room once again summoned monsters. This time, however, it wasn't a Crimson Flame Dragon but an Ice Snow Dragon—a dragon that commanded ice and frost, a far higher-ranked species. The frost dragon Leo once considered contracting for Yukino in the Familiar Forest was a lower subspecies. Which meant this Ice Snow Dragon was far stronger than that frost dragon—and much stronger than the Crimson Flame Dragon they'd fought earlier.
It gave the three of them real trouble.
Against this one, even Rias couldn't destroy it in a single strike. Sona Sitri, meanwhile, found herself in the opposite situation from before—her water-based demonic power, normally her strongest weapon, not only failed to suppress the creature but froze the moment she gathered moisture, nearly trapping her in ice entirely.
Leo once again finished off his opponent first. A massive beam of demonic power swallowed the Ice Snow Dragon completely. He then immediately turned to help Sona, allowing her to narrowly defeat her own foe.
By the time Sona won, Rias finally landed her own Power of Destruction on the Ice Snow Dragon, reducing it to ash and opening the path to the next room.
The second room was filled with traps—specifically a miasma that corroded devils' bodies. The purer one's bloodline, the stronger the effect. Rias and Sona collapsed within seconds, gasping for breath, faces pale, unable to move without unbearable pain.
Leo suffered as well, but only half of his bloodline was pureblood devil. The other half belonged to a human exorcist. Because of that, the miasma hit him far less severely. He could still move, and his demonic power flowed normally.
So Leo unleashed a barrage of demonic power blasts, detonating the miasma throughout the room until it thinned out enough for Rias and Sona to breathe again. After resting a while, they recovered enough to open the passage to the third room.
In the third room, they encountered another trap.
This time, it wasn't miasma—it was something far deadlier to devils.
Light.
Just like the last strike Sharon had used against Yukino, the floor lit up with a massive magic circle of light. Radiant power erupted from it, instantly shattering Rias and Sona's hastily formed defensive magic circles. Only Leo's magic circle held strong, resisting the overwhelming brilliance.
Seeing the danger, Rias and Sona launched counterattacks at the glowing floor—Rias firing a condensed orb of destructive demonic power, Sona shooting a vortex of rapidly spinning water. Their attacks struck the magic circle, obliterating both it and the floor beneath it.
Only then did they clear the third trial.
With three more rooms behind them—four including the first with the Crimson Flame Dragon—Leo was still in decent shape. But Rias and Sona were visibly tired; the strain was starting to show.
Fortunately, when they stepped into the next room, they finally saw the one behind everything.
"Welcome to the Master's Chamber, successors of Eligos, Gremory, and Sitri."
The speaker was a young-looking man dressed in the finery of a noble—yet nothing about him felt refined. His cold smile and the aura around him felt rotten, like something that crawled out of a crypt. He looked under thirty, but compared to Leo and the others, who weren't even twenty, he was clearly older—and his true age definitely wasn't reflected in his appearance.
Devils lived long lives. Judging by his presence alone, he had to be at least a century old.
"So it's you?" Rias stepped forward. "You're the one behind all of this?"
The voice was unmistakable—it was the same voice they'd heard in the very first room of the maze.
This was the man who dragged them here.
"My name is Lafei Trix."
Leo, Rias, and Sona's eyes all sharpened.
"Trix?" Sona narrowed her gaze. "You're a descendant of the Trix family—one of the outside devil houses?"
Outside devil houses referred to devil families not counted among the Seventy-Two Pillars, yet still well-known. Some had once produced extraordinarily powerful devils, some rivaled or surpassed Pillar families in strength, and others simply chose not to involve themselves in Underworld politics.
Only a few remained in the Underworld—families like Mammon, Abaddon, and Belphegor, who withdrew voluntarily to avoid political conflict.
Trix had once been one of them.
But in the present Underworld, their name had all but vanished.
The reason was simple: centuries ago, during the civil war, the Trix family pledged allegiance to the Old Maou Faction and became the direct subordinates of the son of the original Beelzebub—the tyrant who ruled the Underworld back then.
They became his executioners, slaughtering any devil families who dared to resist.
Their massacres earned universal hatred. The reformists targeted them relentlessly until the Sitri House and the Glasya-Labolas House annihilated their clan.
As the next head of the Sitri House, Sona knew this history intimately.
"Correct," Lafei said coldly. "I am the last surviving member of the Trix family—the only survivor."
His glare at Sona brimmed with venom.
"Successor of the Sitri House… the blood running through you makes me wish I could burn you to ash. Not just because your family destroyed mine—but because you dare to stain the name of Maou Leviathan."
"You and your sister are the ones I despise most. You're the people I want to erase from existence."
"Once I heard you were hosting this gathering, I rallied others who shared my hatred for the Sitri House… and created this killing field."
He then turned his spite toward Leo and Rias.
"The both of you as well. One shamelessly claims pureblood status despite being a half-breed. The other inherited the Bael clan's Power of Destruction, just like that impostor Lucifer."
"And you're both close allies of the Sitri successor. Her friends. Her trusted companions."
"Which means you all deserve to die."
His rancor was unmistakable… but Leo's group remained unmoved.
"As expected of a ghost clinging to a forgotten grudge," Rias said, smiling coldly. "No wonder you'd do something like this. A Trix survivor, huh?"
"Indeed." Leo spoke as if Lafei didn't exist. "A family of executioners hated by all devils, opportunists who followed the darkness of the old era. After losing everything, of course you'd seek revenge."
"Too bad. You finally produced a survivor… and instead of hiding to rebuild your family, you came running out here to die."
"Idiot descendants stay idiots, I suppose. No wonder all you can manage is underhanded tricks."
Their words snapped Lafei instantly.
"SHUT UP! Don't you dare insult my family! You know NOTHING—"
His screaming was cut short by Sona's attack.
"The ones who loved insulting others' families were your executioner ancestors," she said icily. "Seems you didn't learn from their downfall. Idiots produce idiots, after all."
She flicked her hand.
A surge of water burst beneath Lafei's feet—silent and perfectly timed—forming countless needle-like spikes that shot upward.
She had prepared this trap from the moment the conversation began.
Against an ordinary High-Class Devil, it would have landed cleanly.
But—
"—Tch!"
A blast of terrifying demonic power erupted from Lafei's body, shredding the water spikes into mist.
"What?"
Sona's expression tightened. Rias's eyes narrowed sharply.
Leo raised an eyebrow, genuinely surprised.
Because the demonic power Lafei released had surpassed the level of a High-Class Devil.
An Ultimate-Class Devil.
Lafei Trix… was an Ultimate-Class Devil.