Reginleiv, Progenitor-san, and I formed a trio and ascended the stairs together. Just as the High Elves had described, we emerged into a massive chamber. As I had expected, the children were nowhere to be found. Instead, three of Zabuton's children were waiting for us. They were the very first group to have climbed the stairs.
"Even though the others moved on, you all stayed right here just like I told you? Good girls. I'll give you a reward later. Steamed potatoes? Sure, you can eat your fill."
I couldn't linger, though. I had to catch up to the children. When I asked the spiderlings what they wanted to do, they decided to follow us while keeping watch on our rear. I thanked them and set off. The path forward was easy enough to understand; we just had to follow the river.
After walking a short distance, we found a narrow bridge spanning the water. This was the "Trial of the Righteous Path." Though it was called a narrow bridge, it was still about fifteen centimeters wide. It seemed easy enough to me. I took the lead, but as I was crossing, I heard a massive splash behind me.
When I looked back, Reginleiv and Progenitor-san had vanished. They had both fallen into the river and looked to be drowning. I started to jump in after them, but then I hesitated—leaping in to save drowning people can be dangerous if they drag you down with them. Before I could make up my mind, the bridge beneath my feet vanished, and I was dropped into the water as well. I had forgotten about the "joint responsibility" rule.
I considered trying to make a floatie out of my clothes, but just then, several actual swim rings came floating down from upstream. I wondered if it was a coincidence, or if the dungeon had provided them out of kindness after seeing my companions struggling. Regardless, I swam over, secured the rings, and delivered them to the drowning duo. The three of us were then swept downstream. Behind us, Zabuton’s children tried to help by extending their silk, but the threads were repelled by some kind of barrier. I told them not to worry about us and to keep moving, but they jumped into the river and came chasing after us anyway.
Being dropped over a waterfall was quite a frightening experience. Once we were back at the start, Progenitor-san used his magic to dry our bodies and clothes while I asked why they had fallen.
"A powerful barrier was erected there, so I was unable to fly," Reginleiv explained. Progenitor-san nodded in agreement.
I understood that they couldn't fly, but I still felt like they shouldn't have fallen just by walking across. They both apologized sincerely, looking quite sheepish. Apparently, they were simply terrible at crossing narrow bridges. I told them to keep their posture straight and look ahead rather than at their feet, then dragged the reluctant pair back for a second attempt. The spiderlings followed us once more. I warned them that they didn't need to jump in after us if we fell again, as it was dangerous.
We retried the "Trial of the Righteous Path." They certainly tried their best, but despite my advice, both of them were hunched over with trembling knees. We ended up visiting the waterfall one more time.
Eventually, we managed to overcome that trial and reached the "Trial of Integrity." We found ourselves in a room filled with floor tiles, with demon statues lining the walls. Each statue held a mud ball. According to the messages left by the groups ahead of us, stepping on the wrong tile triggered the statues to throw. If a mud ball actually hit you, you were disqualified, and the floor would vanish to drop you into the river.
We struggled quite a bit here, falling four more times. Reginleiv and Progenitor-san began to bicker—she blamed his poor intuition, and he grumbled that her claim about the footprints being safe was a lie. I had to step in to keep the peace.
Next was the "Trial of the Hexagon," a series of small rooms filled with doors. We had heard that we could act individually here, but it turned out that once one person passed through a door, it vanished. We were forced to split up. However, since we could look over the layout from a high vantage point before entering, it wasn't too difficult as long as we maintained our sense of direction. We only fell twice. They bickered again—something about a floorless room and a golem chase—but we pressed on.
The next challenge was the "Trial of Silence." We found several groups already there: High Elves, Mountain Elves, Lizardmen, and even some of Kuro’s and Zabuton’s children. Lu’s group and my children were already gone, having moved on ahead. The people here weren't resting; they were in the middle of a trial that required each group to catch a single fish from a pond beside the river.
Fishing was one of my hobbies, so I was ready to show off my skills. However, Reginleiv caught a twenty-centimeter fish in about five seconds. We released it so as not to block others from proceeding, and then she and Progenitor-san practically dragged me away before I could even cast a line. I’ll have to come back here later.
We faced even more trials after that, arguing and reconciling as we went. As long as the three of us were together, we could handle anything. Along the way, I saw Lu’s group and Tia’s group being swept away by the river beside us. Then I saw Urza, Alfred, and Tiselle floating past. They looked incredibly sulky, but they were safe in their swim rings. I called out to them to be careful at the waterfall.
After watching Galf’s group wash away, we cleared two more trials and finally found a large sign: "Final Trial."
We proceeded slowly until we emerged into a bright area. It was a beach, though I didn't recognize the location. A group was waiting for us there, led by the Sea Race Representative—the elderly mermaid I had met back in Shashato City.
"O magnificent challengers!" he greeted us theatrically. "Well done reaching this far! However, here is the final trial! I wonder if you can truly overcome it!"
He then presented us with seafood dishes. It was octopus meat, and it was delicious.
It turned out that the Coastal Dungeon was managed by the Sea Race, and they were the ones who had sent the swim rings down the river for us. I asked why the Sea Race members we met earlier hadn't seemed to know about the entrance. He explained that only a very few high-ranking members knew the truth of the dungeon. Over thousands of years, the knowledge of the trials had largely faded, and the "Final Trial" of sharing a meal had simply become a traditional way for them to resolve external disputes.
"Those who overcome the Final Trial may proceed further," the representative said, pointing toward the shallows.
A Teleportation Gate appeared in the water. I suspected Lu and the others would be trying again soon, so I decided to wait for them there. It would be more reassuring to move forward with a larger group.
While we waited, the next group to emerge onto the beach was the trio of Zabuton's children who had started first. They had cleared the entire thing on their own. They really were impressive.