The Trump Card.

Regal had caught the blow Zegart intended for me.

Did he… save me?

I stared at the skeletal swordsman in surprise.

Zegart also wore a look of shock and confusion.

“…Will you side with Fried, Regal?”

“I no longer know… within myself,” the skeletal swordsman groaned. “My hatred for humans has not vanished. Nor will it ever. But this man—”

Regal turned back to look at me.

“Something is… different about him. When I am with him, my heart feels a little—the ‘heart’ I thought I had already lost feels as though it warms up just a tiny bit.”

“…Hmph.”

“I wish to see what that truly is. Therefore, I cannot allow you to slay the Demon King right now.”

“You speak far too selfishly, Lord Undead,” Zegart grunted with displeasure.

“I cannot offer excuses. But I cannot lower this blade, either.”

Regal raised his broken sword.

The miasma surrounding his body had almost completely vanished.

Pluto End Slash (Hades Blade End)—

In his fight against me, he must have used up nearly all the miasma he had accumulated over thousands of years. He likely had barely any strength left to fight.

Even so, Regal’s fighting spirit hadn’t withered at all.

“I will show no mercy, Fried, Regal,” Zegart stated quietly, turning his gaze to Tsukuyomi. “Do it.”

“Are we deploying That, my lord?”

“In a battle of life and death, you never know what might happen until the end. I will play my trump card all at once right here and crush them with overwhelming power.”

“Its operational capacity is still far from full… but well, as a live-combat test, it is quite fitting,” Tsukuyomi said, raising his right hand toward the sky. “King of Darkness!”

ROOOOOAAAAAAAR!

An eerie roar resounded through the air.

Something slowly descended from the sky.

“What is that…?”

I stared blankly up at the sky.

A black dragon over a hundred meters long, covered in magical armor with a mechanical design.

“The Astaroth Gear—a Demon King Castle defense weapon built to oppose the gods, though it remains incomplete,” Tsukuyomi explained.

A Demon King Castle defense weapon—

Indeed, I had been told about its existence when inheriting duties from the previous Demon King, Yulisha. But I was told that most of these weapons were destroyed in ancient wars and were now useless.

To think it had been repaired…?!

“I activated what had been sealed beneath the castle since ancient times, during the war between the gods and the First Demon King (Velfer). Its operational capacity is thirty percent at most… and yet—”

“Its performance is more than enough to bury you two, exhausted as you are,” Zegart added.

“There is still something else sleeping beneath the Demon King’s Castle—most likely. If I can research it to my heart’s content, and if I can gain the knowledge to do so from that person, then the reward for joining Lord Zegart’s side is more than enough for me,” Tsukuyomi said.

A desire for knowledge, then.

So that was Tsukuyomi’s reason for joining the rebellion.

“I was created as a tool for the former Demon General Izana. But Izana is dead, and now I am free—meaning I shall live according to my own will. Which is to say—”

For the first time, passion filled Tsukuyomi’s voice.

“—I shall pursue my path as a researcher…!”

GYYYYAAAAAOOOOOOO…!

With a screech that sounded like grinding iron, the giant dragon opened its maw.

Flash of light filled my field of vision.

A yellowish-white dragon breath swept across the Inferno City. Buildings vanished all at once, and the black pillars of fire in all four directions of the city were blown away together.

“This power…!”

In an instant, Jiregga was reduced to ruins.

If they had used this in the fight against the Heroes, the battle would have been so much easier.

Why didn’t they use it then?

Naturally, because it was a secret weapon kept for the rebellion—even if it meant sacrificing other demons to the Heroes.

I gritted my teeth tightly.

No, anger can wait for now.

“Regal!”

I rushed to his side and chanted a magic barrier spell. “Lucifer’s Shield!”

However, the barrier flickered and vanished almost immediately after activating.

“Useless, useless! I alone could eradicate you, but now we also have Tsukuyomi and this weapon. There is no way out—”

“—Not yet.”

I hadn’t given up.

As if I ever would.

“I, Regal, Lyrim, and the others—we will all get out of here alive!”

“Then I shall shatter that very hope!”

Zegart raised his fist, his razor-sharp claws glinting fiercely.

I had no strength left to fire magic powerful enough to intercept him.

“We won’t let you! We will protect the Demon King!”

It was Lyrim and the guards who stepped forward.

“Stop, you guys—”

They would definitely be killed!

I dashed forward, trying to step in front of them—

“Ice Blast!”

Suddenly, ice magic flew in from behind.

“Ngh?!”

Hit by a surprise attack of advanced ice magic, Zegart stumbled backward. While a single blow wasn’t enough to defeat him, it clearly dealt some damage.

“Your Majesty, are you unharmed?!”

Someone came running from behind.

That voice—

“Stella!”

A beautiful silver-haired girl clad in black robes rushed to my side.