Entering the cave, the first thing they saw was a wide and long path that extended downward, with occasional sticky substances on the walls that looked rather nauseating.
Tenjo Hikari held a card in his hand, the card illuminated with light, serving as a flashlight to brighten their way forward.
Or should we say downward?
After walking for a while, the cave gradually became brighter, with fluorite everywhere illuminating the surroundings.
As Tenjo Hikari ventured deeper, they gradually began to hear voices.
There were only two or three voices, sounding somewhat familiar.
As they continued forward, the voices became clearer, and the cave grew exceptionally bright.
Soon, they passed through a long passage and finally reached a spacious underground cavern.
The cavern was immense, extending beyond sight, and it may not be smaller than the forest area.
Looking from afar, Tenjo Hikari could see a few students sitting on the ground, discussing heatedly.
"So why didn't you use Polymerization to fuse Ultimate Giant at that time?"
"I didn't have enough materials. I didn't have enough Ancient Gear cards in my deck!"
"Just use Gaia the Dragon Champion then!"
"I didn't have the materials either—"
"You clearly have Monster Reborn and revived a Gladiator Beast!"
The students chattered on, not even noticing Tenjo Hikari's arrival.
"Huh?" Serena was somewhat surprised.
Tenjo Hikari breathed a sigh of relief.
At least the people here were fine.
The place was indeed isolated and remote compared to outside, apparently unnoticed by the Dark World Archfiends.
"Zaka, how have you all been?" Tenjo Hikari raised his voice, calling out to them.
Upon hearing Tenjo Hikari's voice, they finally snapped back to their senses and looked toward the cave entrance.
"Brother Hikari?"
"Minister!"
Kagurazaka jumped up and waved at Tenjo Hikari. "Hey, Minister, you're here too?"
The three were none other than Kagurazaka and the Fusion Department trio, usually in charge of the Fusion Department bar, so their relations were good; they were traveling together at the Critical Point, and from a distance, Kagurazaka already had three badge marks, which should allow him to pass the exams smoothly.
Tenjo Hikari talked to them for a while, asking about their situation and explaining why he specifically came to find them.
Upon hearing about spirits attacking humans, the three were shocked, feeling both relieved and scared.
Relieved because they had been in this cavern all along, dueling with the spirits here, thus unaware of the outside events.
Scared because their food supply was almost depleted, and if Tenjo Hikari had been a day or two late, they would have been forced outside, potentially unprepared for Archfiend attacks.
Due to this being underground, Kaiba Company's communication wasn't set up, so while in the caves, they couldn't contact external classmates or know what was happening outside, remaining stuck there, dueling with the spirits.
However, when Tenjo Hikari asked them about the spirits here, they collectively clammed up, teasingly withholding information, saying only that Tenjo Hikari would surely like them.
"As long as the Minister is here, Kagura, we can challenge for another day, right?"
"No way, there might be other classmates trapped in other places, what if we're late?"
Kagurazaka nodded, disagreeing with the first friend's statement.
"We shouldn't be so stringent." Tenjo Hikari opened the map and roughly pointed. "I came to the most remote location; other places have other people and spirits for rescue, and overall, everything is happening simultaneously.
I can't possibly go everywhere alone, whether in terms of time or resources."
Tenjo Hikari was very clear about this, so initially, besides emergency rescue, he assisted Kaiba Company in reorganizing.
"Is that so? Then we can stay here for another day!" Kagurazaka became excited.
Tierra couldn't resist nudging Tenjo Hikari with her elbow, curious about what was making these Fusion Department students so persistent.
Frankly, Tenjo Hikari was curious too.
Though the Fusion Department can't choose numerous basic decks, they have ample experience, especially Kagurazaka, a wealthy young master himself, not renting cards like Gu Jujie but owning them.
He was able to acquire half of Tenjo Hikari's Fusion Deck. What kind of card could make them so persistent and excited?
Kagurazaka loaded the deck into the slot, stood before a cave pool, and shouted, "Hey————"
"Lord Dragon King————"
"We're ready!"
In response to his call, the pool began to tremble. Soon, one by one, small spirits flew out from the surroundings.
They emitted fluorescence, with slimy bodies, surrounding them from every direction.
They had tiny wings, their slimy bodies resembled mud, shaped like dragons, mouths opened, happily and curiously shouting, "There are new humans, new humans~"
From the nearby walls, the cave ceiling, various bizarre little spirits emerged, all excitedly awaiting a "show."
With these little dragons encircling, the "pool" below started bubbling, ascending slowly, morphing into a large green mud dragon.
Tenjo Hikari widened his eyes slowly.
Unexpectedly—
It was!
The Mud Dragon King!
Upon the Mud Dragon King's appearance, it slowly opened its mouth, ancient voices emanating from within: "Humans, are you here to challenge me again?"
"Exactly!" Kagurazaka said excitedly, eyes filled with fighting spirit and enthusiasm, "This time, I must take home a Beast King!"
Tenjo Hikari suddenly realized.
So that's why!
No wonder Kagurazaka kept teasing, saying Tenjo Hikari would surely enjoy the spirits here!
It turns out it was [Swamp]!
Tenjo Hikari couldn't have imagined that beneath the cave would be a "swamp"!
This must be the Spirit World, so peculiar indeed.
Any member of the Fusion Department seeing this place would probably never want to leave.
Because anyone familiar with Fusion-Related Cards would surely realize that the monsters in this swamp could likely be used interchangeably as Universal Fusion Material!