Travelling to the mountains took a long detour downwards in one step. Rino and Mutt were running away from the angry group of six-armed monkeys who were addicted to bones. Rino simply looked like a tasty treat and easy prey, so they had to escape when the monkeys started walking towards them on water. 

Mutt carried his master dutifully, not minding the burning sun and purple flames burning his shadow body. He dodged and snarled when the monkeys came too close to his master, and Rino held onto his mount tightly in fear of getting thrown off. 

He could use magic to ward these creatures off, but Rino wasn't here to create trouble or make enemies. Killing the monkeys might attract a more troublesome foe before arriving at their destination, so Rino refrained from doing so and urged Mutt to go even faster.

Looking back, that was his mistake.

Thanks to the poor lighting in the jungle caused by the thick foliage, Mutt could not see where he was going, and they ended up plummeting into a hole in the ground.

Why was there a hole in the ground in the middle of the jungle? Even the six-armed monkey tribe could not understand what happened. As soon as Rino and Mutt fell in, the ground collapsed and covered the small entrance they fell from, sealing it from any light sources above.

Despite the terrible situation, the silver lining remained that they no longer had angry monkeys chasing them. Rino would deal with this detour any day over confronting the dangers of the jungle above. Then again, he had no idea if it was safer underground. Going by the logic that most living creatures in this world preferred to live above ground, Rino would take his chances in this place.

Summoning fire magic in this place was a mistake. Rino quickly threw up a magic barrier to protect himself from the powerful explosion. Mutt hid in his master's shadow on instinct at that smell. He knew this smell a little too well but failed to warn Rino before the lich lit a fireball.

"That's exploding gas from the earth leaks," Mutt explained to Rino, who was trying to make out where the ground was in the dark.

"You could have told me earlier," Rino scowled but righted himself after a minute, dusting the dirt that collected in his hood.

The lich walked around in the dark and felt the edges of the wall he was blown into. This mine was huge! He couldn't believe his luck at finding such a gem in the middle of the jungle, but Rino wasn't going to question how this world worked. He just hoped to find some dwarfs around even if he was frustrated at not being able to see.

Rino thought about it as he walked through the cave without sight. He could feel the solid ground changing into something mushier. The sludge-like ground made progress slow, and Rino did not want to think about the dull smells invading his senses. Mutt was cringing so hard in his shadows that the lich took pity on the wolf and let him remain in there until Rino found a way out of here. He considered risking burning his body by borrowing light magic from his world tree self when there was a faint light from up ahead.

There was a familiar tingling in his bones as he approached the light, and Rino recognised what the feeling was. It was something he missed a lot by travelling in this jungle and by the river. The air was very stale to a magician like him. It was devoid of mana and life everywhere he went after the night he spent holed up sleeping in a shallow cave.

Mana!

Excited, Rino ignored how the sludge-like liquid was reaching his exposed waist. He marched onward to the glowing green light and rejoiced when his efforts paid off. Like a diver in need of oxygen, Rino ran. He could summon Mutt to reach the end of this dark road quicker, but he wasn't thinking as his feet carried him.

Finally meeting the source of the green glow, Rino marvelled at the crystal he found. It was huge and reminded Rino of mithril back in the royal mines. However, Mithril was dark blue and not turquoise green.

There was no denying that this crystal was the source of the mana. It glowed and pulsed lightly as if it was breathing, making Rino believe that the rock had to be similar to the space rock he found. He never knew that there were mana-emitting rocks and crystals in this world or why they existed. According to Noir, the origin of mana was the very base form of life. It contains a soul and fragments of it that would condense into a soul.

He couldn't understand the lack of mana presence above ground and the overcompensation of it underground. What were these crystals, and why did the jungle above create such hostile creatures?

The more Rino discovered about this world, the less he seemed to understand. However, he was now certain that this was a valuable cave and hoped he could somehow remember where this cave was after finding a way out.

Nevertheless, Rino used dark magic to hack a smaller piece of this large green glowing crystal from the main body. The little piece broken off from the big crystal body continued to glow lightly in Rino's hand, so the lich stored it away safely in his shadow sack. He still had about eight days left to find a suitable location for his town. That should be plenty of time, even if there was no longer enough time for the recreational activities he had in mind.

He should find a way to get out of here now and pick a place close enough for him to return to this cave. This curious mana-emitting crystal would require a little more studying, and Rino did not want to let this cave exploring opportunity go, not when he had more questions than answers.