Immortality and cultivation: Heaven rewards diligence, and success is inevitable.

The volcano is very tall, estimated to be 300 zhang (approximately 150 meters).

The mountain is made of black basalt, and its surface is covered with cracks, resembling a dried-up riverbed.

At the top of the volcano, thick smoke and flames spew out, and the heat is so intense that you can feel the scorching heat even a kilometer away.

At the foot of the mountain, there is a dark cave entrance, resembling a giant mouth.

Steam billowed from the cave entrance, making it feel like a steamer. Inside was the lair of the Crimson Lion.

Jiang Shi and his three companions stopped outside the cave entrance.

"The Crimson Flame Lion is at the deepest part of its lair," Huo Lie said. "After entering, you'll first pass through a passage, at the end of which is a large cave, where the Crimson Flame Lion resides. The Marrow Cleansing Spring is even deeper within the cave, requiring you to traverse the Crimson Flame Lion's territory."

As a disciple of the Burning Heaven Sect, Huo Lie was naturally familiar with this type of cave.

Previously, in the fire-elemental secret realm controlled by the Burning Heaven Sect, there were also fierce spirit beasts guarding the Marrow Cleansing Spring Cave, but they were later eliminated by the Burning Heaven Sect.

"In other words, you have to defeat the Crimson Flame Lion to reach the Marrow Cleansing Spring," Jiang Shi said.

"Yes." Huo Lie nodded. "There is no other way."

Feng Yiran walked to the cave entrance and glanced inside. It was very dark inside; his spiritual sense was blocked by the fire poison miasma.

He could only sense a range of ten zhang (approximately 33 meters).

"There are signs of a struggle inside," Feng Yiran said. "It seems that the people from the Five Elements Demon Sect have already gone in."

Jiang Shi also extended his spiritual sense.

His spiritual sense was slightly stronger than Feng Yiran's, and he could perceive up to fifteen zhang (approximately 33 meters).

There were charred marks on the walls of the passageway and bloodstains on the floor, but the body had already been disposed of.

"That's right, it was people from the Five Elements Demon Sect who went in." Jiang Shi observed for a while and then said, "Judging from the wounds on the corpses, they were inside for less than half an hour."

Shui Lingxi frowned: "They're ahead. If we follow them and rush in, we'll definitely be ambushed."

"Not necessarily," Huo Lie said, shaking his head.

"They also need to fight the Crimson Flame Lion, which is at the late Golden Core stage. The five of them might not be able to defeat it, and even if they do, they'll have to pay a price. We'll go in after they've finished fighting it off."

"The fisherman benefits?" Jiang Shi's eyes lit up upon hearing this, and he laughed.

"Yes, they and the Crimson Flame Lion are both severely injured, then we'll make our move," Huo Lie said.

"This Crimson Flame Lion is even more powerful than I imagined. It seems the Five Elements Demon Sect is going to suffer a great loss this time!"

Using a secret technique, Huo Lie discovered the situation inside the cave: the Crimson Flame Lion had actually broken through to the peak of the late Golden Core stage!

They're not far from reaching the Nascent Soul stage!

According to the records of these major sects, this Lesser Five Elements Secret Realm had never undergone such changes before!

"I see. It seems we don't need to worry about attacks from the Five Elements Demon Sect anymore!" Jiang Shi said.

The four waited outside the cave entrance for an hour.

A roar came from inside the cave; it was the Crimson Flame Lion.

There were also explosions, the sound of attacks from the Five Elements Demon Sect, the sounds growing more intense and frequent.

"They've started fighting," Huo Lie said, glancing into the cave every now and then, looking concerned.

Half an hour later, the sound suddenly stopped.

It didn't gradually weaken; it suddenly stopped.

Jiang Shi quickly walked over and said, "Let's go."

The four of them immediately stopped waiting and rushed into the cave together.

The passage slopes downwards and gets increasingly hot.

The walls were inlaid with luminous minerals, which illuminated the passageway in a dark red glow.

The air was filled with the smell of magma, and you could feel the ground shaking beneath your feet.

Having walked less than a hundred steps, a beast's roar came from ahead. (The novel, "Eternal Life and Immortality: Heaven Rewards Diligence, Success is Surely Within Reach," features stunning writing and a gripping plot.)

Crimson Flame Lion.

Then came screams.

The sound of fire burning the sky.

Jiang Shi quickened his pace and rushed out of the passage.

Before us lay a huge cave.

The cave is hundreds of feet in diameter, and the top is so high that you can't see the top.

The four walls were made of black basalt, which shone brightly from the heat.

In the center of the cave is a lion, the size of an ox, its body engulfed in golden flames.

Its fur is crimson, its eyes are golden, and its pupils are vertical.

Flames danced on its four claws, and a fireball clung to the end of its tail.

Crimson Flame Lion, late stage of Golden Core!

With a single swipe of its claw, the Crimson Flame Lion sent Huo Fentian flying! Huo Fentian coughed up blood, sustaining severe injuries!

On the other side, Mu Qingqing and Shui Wuhen were still fighting.

Mu Qingqing's vines wrapped around the Crimson Flame Lion's hind legs, while Shui Wuhen's ice spear pierced towards the Crimson Flame Lion's eyes.

They had to stop the Crimson Lion from continuing its pursuit of Fire Sky.

The Crimson Flame Lion shattered the ice spear with a single claw, and its tail swept across, sending a fireball crashing into Shui Wuhen.

Shui Wuhen was thrown into the air, crashing into the wall and spitting out blood.

Mu Qingqing wanted to retreat, but the Crimson Flame Lion turned around and spewed out a golden flame.

The flames burned through the vines and reached Mu Qingqing's arm.

Mu Qingqing screamed in agony as the skin on her arm was charred.

The thick earthen wall rushed forward, blocking the Crimson Flame Lion.

The earthen wall was three feet thick, but the Crimson Flame Lion shattered it with a single swipe of its claw.

The thick soil was hit by gravel and fell to the ground.

Jin Bufan stood at the very back, his face ashen.

His golden longsword was stuck in the ground, the runes on its blade flashing.

He was gathering his strength, the energy of metal condensing at the tip of his sword.

"Retreat!" Jin Bufan shouted.

He drew his sword, and a golden sword aura slashed towards the Crimson Flame Lion. The sword aura struck the Crimson Flame Lion's head, leaving a wound. The Crimson Flame Lion, in pain, staggered back a few steps.

Mu Qingqing dragged the heavily injured Huo Fentian and ran outside.

Shui Wuhen slid down the wall and was helped by Tu Hou to run outside.

Jin Bufan covered the rear, unleashed two more sword strikes, and then turned and ran.

The five retreated from the other side of the cave, instead of using the passage Jiang Shi and the others had entered through.

Upon seeing Jiang Shi and the others enter, Jin Bufan immediately decided to abandon the battle.

Jin Bufan originally thought he could easily kill the Crimson Flame Lion, and then take advantage of the fact that the underground cave was difficult to escape from, to trap and kill Jiang Shi and the others.

However, Jin Bufan never expected that the Crimson Flame Lion would evolve and become so powerful.

Jin Bufan does have methods to deal with enemies in the late stage of the Golden Core realm, but he doesn't want to use them in this situation!

The Crimson Lion did not give chase.

It stood in the center of the cave, its golden eyes fixed on Jiang Shi and his companions.

Huo Lie swallowed hard: "It's even more powerful than I imagined. Even the Five Elements Demon Sect members are no match for it!"

Feng Yiran gripped his sword tightly: "To fight or not?"

Jiang Shi looked at the Crimson Flame Lion. The Crimson Flame Lion was also looking at him, its golden vertical pupils devoid of emotion, only filled with killing intent.

"Fight, of course we should fight," Jiang Shi said.

"But we won't fight head-on. Huo Lie, you hold it off from the front. Feng Yiran, you look for opportunities from the side. Shui Lingxi, you harass it from behind with ice magic. I'll find an opportunity to trap it with the Mountain and Sea Banner."

Jiang Shi addressed the group, and they nodded in agreement, acknowledging his division of labor.

The Crimson Flame Lion fought for over an hour against the five Golden Core stage cultivators of the Five Elements Demon Sect.