The rift of light was larger than they had imagined, and father and son successfully squeezed through it.
Yu Xuan looked up ahead. A stretch of parched, cracked earth met his eyes, with red magma flowing through the fissures and red mist rising from them.
The sky was shrouded in red, with no sun or moon, only rising red mist.
Not a blade of grass grew here; there was only a scorching, desolate landscape.
"Come on, let's take a look ahead." Yu Yuanzhen walked in front and raised a hand to beckon him along.
Yu Xuan nodded slightly and hurried after him.
After walking some distance, the two saw the remains of several Soul Beasts and humans. They even picked up a thousand-year Soul Beast right leg bone.
Neither of them thought much of it, but it was still a decent find.
A volcano appeared ahead of them, and directly in front of it stood a massive stone gate some fifty meters tall.
Yu Xuan walked up to the stone gate and looked at Yu Yuanzhen beside him. "It looks like this secret realm was probably created by someone."
Yu Yuanzhen stepped forward and touched the stone gate, instantly feeling its scorching heat.
"I wonder how this stone gate opens. I don't know if it can be blasted open by force."
Yu Xuan thought for a moment, then suggested, "Father, why don't you give it a try?"
"All right, stand back a little." Yu Yuanzhen waved a hand.
Yu Xuan hurriedly retreated more than fifty meters.
Yu Yuanzhen's Eighth Soul Ring lit up beneath his feet, and Soul Power rippled outward.
"Eighth Soul Skill-Soaring Dragon Heavenly Lightning Explosion!"
A vast mass of thunderclouds suddenly gathered in the sky, and countless bolts of lightning in the shape of dragons struck down upon the stone gate.
When the dust cleared, both men looked at the stone gate, only to find it completely unscathed.
"Sigh, I don't know what this stone gate is made of, but it's incredibly sturdy. Since my Eighth Soul Skill did nothing but make a noise, I doubt my Ninth Soul Skill would be of any use either." Yu Yuanzhen shook his head and sighed, feeling there was no hope.
"Why don't I try?" Yu Xuan was silent for a moment before stepping forward to speak.
"You? Even I can't open this stone gate. What could you possibly do?"
Yu Yuanzhen didn't think he had any way to open the gate, but he didn't stop him either.
Yu Xuan walked up to the gate, pressed one hand against it, and released his Fire Dragon King Martial Soul.
"Rumble-"
As if Yu Xuan's Martial Soul had touched upon some rule, a deep sound came from the stone gate.
"Look, the stone gate is going to open on its own." Yu Xuan turned to his father and gestured with a smile.
Just as I thought. Since this secret realm drew me here, how could I possibly be unable to get in? This place most likely has something to do with the Fire Dragon King.
Yu Yuanzhen: "..."
He was speechless. His Soul Skill had done nothing but make a noise when it struck, yet the gate had opened on its own when his son merely released his Martial Soul.
With a rumbling scrape, the massive stone gate slowly parted to either side.
A stone platform appeared inside. The two walked closer and saw that on the platform was... a scale?
It was a scarlet scale, edged with faint golden flame patterns, with some indecipherable symbols engraved on its surface.
Yu Yuanzhen rubbed his chin and said, "This is a dragon's reverse scale. Its color is much like the scales of your Fire Dragon King."
"So, this is the Fire Dragon King's reverse scale?"
Though Yu Xuan had asked the question, he was already almost certain of the answer.
Yu Yuanzhen said gravely, "Very likely!"
Yu Xuan picked up the scale without any resistance, and a stream of information suddenly flooded into his mind.
Fire Dragon King Reverse Scale.
In a moment of crisis, it would automatically protect its owner, withstanding a full-force attack below the god level for five seconds.
The reverse scale was the key to unlocking the treasure of the Mystic Fire Secret Realm.
This Fire Dragon King Reverse Scale can protect its owner too?
Yu Xuan froze for a moment.
And what is that Mystic Fire Secret Realm?
Perhaps, after we get out, I should find a time to ask the Fire Dragon King at the Ice and Fire Yin Yang Well?
"Xiao Xuan, what are you thinking about?" Yu Yuanzhen looked at him, his face full of curiosity.
Yu Xuan said, "Father, this reverse scale really is the Fire Dragon King's reverse scale. It has an extraordinary ability, and it's also the key to a treasure in another secret realm."
"A treasure in another secret realm?" Yu Yuanzhen raised an eyebrow. Rather than asking about the reverse scale's ability first, he pressed on, "What kind of secret realm is it?"
Yu Xuan shook his head and said, "I don't know. This scale didn't say."
"Very well. Put the reverse scale away for now. Let's explore the secret realm some more and make sure there's nothing else good before we leave," Yu Yuanzhen suggested.
Yu Xuan said, "Father, you could go up the volcano and take a look. Focus on the area above this gate. It's close to the reverse scale, so over tens of millions of years, perhaps something has grown there."
Yu Yuanzhen's eyes lit up. "You have a point. I'll go up and take a look."
With that, a pair of dragon wings unfurled behind him, and he flew upward.
Before long, he had a vermilion plant in his hand.
After landing in front of Yu Xuan, Yu Yuanzhen raised the plant in his hand and said, "A herb that looks a lot like spinach was growing at the edge of the crater above that gate."
"Spinach?" Yu Xuan looked at the herb in his father's hand. Sure enough, it really did look quite a bit like spinach.
That meant this plant wasn't the Infernal Delicate Apricot.
He remembered the original work describing the Infernal Delicate Apricot as resembling a cabbage, whereas the plant before him looked like spinach...
Still, since it could grow in such a harsh environment, it was probably an Immortal Herb. Even if it wasn't, its grade would be close.
Father and son made another circuit of the ruined secret realm. Apart from picking up a ten-thousand-year skull near some scattered Soul Beast remains, they found nothing else.
Yu Yuanzhen stroked the ten-thousand-year skull and chuckled. "Just this ten-thousand-year skull and that Thousand-Year Soul Bone alone have made this trip to the secret realm worthwhile."
"It's a pity this ten-thousand-year skull probably isn't a Wisdom Skull. Once we get out, we'll test it to see what Soul Skill it comes with."
Yu Xuan said, "Those Soul Beasts and humans probably wandered into this secret realm by mistake. They couldn't find a way out, so they were trapped here and eventually starved to death."
"That's much the same as what I thought."
Yu Yuanzhen nodded slightly and said gently, "Xiao Xuan, this ten-thousand-year skull is quite good. It's probably at least forty thousand years old."
"If you can't find a suitable skull in the future, fuse with this one. I'll keep it for you for now. As for the remaining Thousand-Year Soul Bone, we'll reward it to a disciple who has contributed to the sect."
Yu Xuan felt warmth in his heart and chuckled softly. "Sorry to trouble you, Father."
After confirming that there was nothing else of value in the secret realm, father and son returned to the entrance where they had come in.
Yu Yuanzhen reached toward the rift of light, only to discover that he could no longer pass through it.
"We really can't get out. That makes sense. If it were possible to leave, those Ten-Thousand-Year Soul Beasts wouldn't have been trapped here until they died."