The battering at the entrance grew more intense, cracks in the stone wall multiplying. Old Stone gripped his flying sword, palms sweating. Gu Xiuyuan stared at the entrance, mind racing.
"Boom!"
Another rock shattered, fragments flying. A star beast's claw reached through the gap, wildly grasping. The claw was basin-sized, nails black and gleaming, flashing coldly in the firelight.
Old Stone retreated in fear. Gu Xiuyuan stepped forward, stuffing his incendiary bomb into that claw.
"Sss——"
The star beast yelped in pain, retracting its claw. The bomb was carried out, landing outside.
"Boom!"
Flames exploded, several beasts screeching. But the explosion was limited, only lightly wounding them, instead provoking their ferocity.
Battering intensified.
Gu Xiuyuan retreated, telling Old Stone: "Too many, can't fight head-on. Need more materials."
Old Stone looked at the ore powder pile in the corner, the oil jar, gritted his teeth: "Master, tell this old man what to do, I'll obey!"
Gu Xiuyuan rapidly scanned the cave. Besides ore powder and oil, there were some dried herbs, spare torches, rag pile. All usable.
"Bring everything burnable," he said. "Quickly."
Old Stone immediately set to work, moving all those items before Gu Xiuyuan. Gu Xiuyuan mixed explosives while observing the entrance's condition.
Another rock shattered, stone wall only a thin layer left.
"Master, almost out of time!" Old Stone shouted.
Gu Xiuyuan didn't answer, just quickened his pace. He divided oil into three portions – one thick paste, one thin paste, one unmodified. Then divided ore powder into coarse and fine, mixing coarse with thick paste, fine with thin paste.
Finally, he took out the three small crystals from star beast bodies, crushed them thoroughly, mixed into the explosives. Those were found after killing beasts days ago, kept aside, now unexpectedly useful.
"Hope this helps somehow," he murmured.
Just then, the stone wall finally gave way, "crashing" down.
Over a dozen star beasts surged in, bloodthirsty maws inches away. The stench was overwhelming, nearly suffocating.
Old Stone yelled, thrusting his sword at the nearest beast. Though only Foundation Establishment, centuries of cultivation meant his flying sword was well-honed, piercing the beast's eye, sending it screaming to the ground. But more surged forward.
Gu Xiuyuan lit an incendiary bomb, hurled it into the pack.
"Boom!"
Fireball exploded, several beasts blasted bloody. But the leader only shook its head, continuing forward. It had lost one eye, but ferocity undiminished.
Gu Xiuyuan gritted his teeth, lit second, third... bombs exploding in the cave, flames and smoke filling the air. Star beast screams rose and fell, but too many – kill one, two more charge.
Old Stone's sword had broken halfway, his body scratched multiple times by beast claws. But centuries of cultivation meant his spiritual energy was deep, each thrust carrying power, barely able to hold back the Golden Core leader. His broken sword still left marks on the leader's scales with each spiritual-infused thrust. The leader, pained, couldn't fully charge at Gu Xiuyuan.
"Master!" he shouted. "You go! This old man will hold them!"
Gu Xiuyuan didn't move.
He stared at those beasts, his eyes frighteningly calm. He saw Old Stone desperately holding them back, and saw old wounds under the leader's scales – from the previous explosion, scales not yet healed.
"One more," he said.
He lit the last incendiary bomb – the one with crushed crystal powder. Hurled it at the leader.
The bomb arched through the air, landing at its feet.
"Boom——"
This explosion dwarfed previous ones. Shockwave blasted surrounding beasts away, the leader flipped over, smoking. It struggled to rise, but its legs were broken. Old Stone seized the moment, thrusting into its remaining eye, piercing through to the brain.
The leader emitted a piercing death cry, finally still.
The remaining beasts finally panicked, screeching in terror, turning to flee.
Gu Xiuyuan leaned against the wall, gasping. The Purple Flame Heart was almost dim, vision darkening intermittently. During the battle, he'd used elemental vision multiple times to observe beast weaknesses, energy consumption huge.
Old Stone slumped on the ground, his broken sword beside him. Several wounds bled, but his face held post-battle joy.
"Master..." he smiled weakly. "We... won?"
Gu Xiuyuan nodded, unable to speak.
After a long time, he recovered enough to approach Old Stone, check his injuries. Wounds were deep, but not life-threatening. He tore strips from his own clothes, helping bind them.
"Master, you're wounded yourself," Old Stone said.
Gu Xiuyuan looked down at his hands – several scratches, but none deep. He shook his head: "I'm fine."
Old Stone looked at him, eyes full of gratitude.
"Master, you saved this old man's life again."
Gu Xiuyuan didn't answer, just continued bandaging.
---
Daybreak, the two began clearing the battlefield.
Seven star beast corpses in the cave, including the leader. Gu Xiuyuan scanned with elemental vision – the leader's body had a fist-sized crystal core, energy fluctuation strong. Others also had small crystals, but much smaller.
Old Stone cut open the leader's head, took out that dark golden crystal core. Surface smooth, inside faintly visible complex patterns, like natural formations.
"Star beast crystal core!" Old Stone trembled with excitement. "This old man only heard of them, never imagined one! One like this, could trade for at least five hundred low-grade spirit stones!"
Gu Xiuyuan took the core, examined carefully. Crystal lattice arrangement perfect, inside almost no impurities, energy flow smooth. Those complex patterns, layer upon layer, held some pattern.
"Interesting," he murmured.
He checked other beasts – though no cores, their bodies had many metallic residues. He had Old Stone collect all, might be useful later.
This finished, it was midday. Two suns overhead, ground scorching hot.
Gu Xiuyuan stood at the entrance, looking at the beasts' escape trail, lost in thought. They came from deep in the mine, suggesting more star iron ore there, possibly more beasts. If he could go deep into the mine, perhaps find more resources.
But the danger was obvious.
Old Stone came beside him, following his gaze, asked: "What is Master thinking?"
"The mine," Gu Xiuyuan said. "I want to go in and see."
Old Stone paused, then didn't dissuade, just said: "This old man will go with you."
Gu Xiuyuan turned to look at him.
Old Stone grinned, revealing missing teeth: "This old man's life was saved by Master. Where Master goes, this old man follows."
Gu Xiuyuan looked into his eyes, those cloudy old eyes held something new – trust, resolve.
"Good," he said.
---
Back in the cave, they began preparations.
Gu Xiuyuan packed remaining oil, ore powder, spirit stones, had Old Stone find spare swords – mediocre quality, but better than nothing. He made simple water bags from beast hide, filling with water and reagents. That sulfuric acid bottle was half full, sodium carbonate enough for several uses, he carefully stored them.
Old Stone unearthed a worn map, pointing at a mark: "This is main mine entrance, this old man usually mines the outer areas. Further in, it's said there are three levels, first layer ordinary star iron ore, second layer higher-grade ore, third layer... no one's ever descended."
"Why not?"
Old Stone lowered his voice: "Because those who went, never returned."
Gu Xiuyuan thoughtfully.
"What's in the third layer?"
"Unknown." Old Stone shook his head. "Some say more powerful beasts, some say ancient ruins, some say teleportation arrays to other worlds. Anyway, those who entered, none emerged. This old man when young, knew a few fearless ones who went, never seen again."
Gu Xiuyuan nodded.
"Then first, explore the first layer."