There was limited knowledge on the Arcane Abyss, but it was said to be separated into eighteen layers. The first three layers were filled with hidden contraptions and spell formations. The next three were the homes of deadly, magical beasts. Then, the next two layers were locations of treasures, ancient spells, and ancient texts. The remaining ten layers were covered in secrecy, but were theorized to contain the legacy of the mysterious magus.

Yang Yang confronted the many blockades with ease. Although the spell formations were nothing difficult, they were more tedious to unravel or break than the very first spell formation. 

Occasionally, he would consume medicinal pills and mystical elixirs to recover his magical power. However, he soon passed them all and entered the Fourth Layer. He took out his legacy student medallion and activated it. 

All students in the institute had the right to leave a life-token inside the Hall of Student Assessment after receiving a student medallion. Life-tokens not only contained records of the students’ achievement, but also connect to their life force. If any student’s life-token were dimmed, then it would indicate that they died and their student medallion was on their person, it would also show how they died. 

Yang Yang was given replicas of the missing legacy students’ life-tokens, which he placed into his own student medallion. Now that he was over the first three layers, there were less interference between his medallion and the medallions of the other students. When he channeled magical power into it, seven distinct auras oozed out with some auras stronger than others. Clearly, there were some students closer to him than others. 

Yang Yang smiled and proceeded to follow the trace of the strongest aura. If he managed to get close enough, then the aura of his medallion might be picked up by the other students as well. 

The Fourth Layer was filled with millions of caves that aligned into a giant labyrinth. Blue crystals stuck out of the cave walls and dimly lit the labyrinth. 

Along the way, Yang Yang would spot magical beasts that lurked deep within these caves or emerged from the walls. However, they were usually Marker level beasts so they hid themselves when they saw him. Even Virtual Aspect level beasts fled from Yang Yang and his mighty warship. 

Although the caves were complex, he had a detailed map that marked seventeen different paths a person could take to descend onto the next layer. 

The warship smoothly and quietly flew through the caves. Yang Yang walked near to the walls and grabbed an ore of the blue crystal. After the blue crystal ore was removed, it glowed even brighter. Magical power rapidly pulsed out of the crystal ore, and returned to the cave. 

"So this is the strange 'Arcane Sapphire'. It's clearly a magical crystal, but it can not contain its dense magical power when taken out of the source. This is a treasure mine of magical crystal, but it can not be easily obtained. If I manage to relearn Space Magic then I might be able to harvest them all, and then complete this mission with a profit in hand. What a shame." Yang Yang crushed the blue crystal ore, and it blasted out a shocking amount of magical power that was quickly absorbed into the surrounding. 

Yang Yang went back to the center of the ship and enjoyed the view. 

......

Three magi in black cloaks were speeding across the cave labyrinth of the Fourth Layer on a blue warship. Each of them carried an aura of evil and reeked of blood. They also wore masks, which added menace to their already horrifying presence. 

"Captain," one of the evil magi asked, "What do you think ate one of the Arcane Sapphire this time? The Blue-Blooded Gophers or the Mountain-Eater Worms? Last time I picked the former and I won the bet so I'll go with the worms this time." 

"Piss off. No one's going to bet anything with you." The evil magus in front said in a raspy tone. "Whatever it is, it won't get far. Since it's desperate enough to dare eat our Arcane Sapphires, it's probably too weak to right now and is slowly recovering its strength. Hopefully it's a Arcane-Devouring Serpent. One of those are worth over a hundred gophers or worms. We'll be heavily rewarded by the cult and can leave this goddamned layer for the first time in twenty years!" 

"Don't get your hopes up, captain. We'll probably have to fight tooth-and-nail against an Arcane-Devouring Serpent and will probably have to fight the other squads." The other evil magus pessimistically said. "We already lost seven men. Our squads is definitely the weakest out of all the squads in the fourth layer. We'll just get screwed backward." 

"Shut up." The other two retorted. Suddenly, the blue warship spoke out in a mechanical voice. 

[Attention: An undocumented, Spiritual-tier warship has appeared within ten kilometers. Danger Level: 9] 

"What!?" The blue warship determined danger from a scale of one to ten; nine meant extremely dangerous. The captain took out a magical device in the shape of a compass and saw a tiny blue dot that was ten pixels to his squad's east. "Holy crap! That's in the same direction as where the Arcane Sapphire was destroyed!" 

"No way. Could it be that someone from the outside has arrived?" 

"Turn it around! Turn it around!" 

The blue warship shifted direction and sped toward the direction of the other warship. The three evil magi were sweating from anxiety, but were also shaking from excitement. They stayed silent, as though they were worried that any sound they made would destroy their thoughts and hope. 

However, when saw a young man with black hair and green eyes aboard a black warship that was as strong as their own, they began to howl with delight. 

"Gold! Gold! We've struck gold!" 

"Hahahahah! We came for copper, only to find gold!"

"Capture him! He's way more valuable than any Arcane-Devouring Serpent!" 

The three evil magi jumped from their ship onto Yang Yang's. Without the slightest hesitation, they cast their strongest spells at him. Yang Yang smirked with a sharp glint in his eyes.