"This is very interesting though. If you think that this was created as a simple way to at least open those doors, the civilization had to be extremely sophisticated… *Growwwl*"
"...and that reduces the possible culprits by a lot. There aren't many that could possibly leave such a legacy… *Growl*"
"Yes… if it's them… it would make sense. And in that case… then it requires… *Growwl* I need to use the restroom!"
Sai was getting desperate. Beidou wouldn't sleep no matter how long he waited, but he could no longer wait. He decided to face it like a man.
She had clearly been using a part of the dark corridor as her private place, though he had not managed to catch her in the act so far. Not that he wanted to. And Sai was using somewhere near the entrance, as it had at least a little bit of light from the engravings on the door.
"Beidou, I'm going to go over there. Don't follow me."
"Hm? Sure."
Sai came back refreshed, and shirtless.
"You-"
"Don't ask."
"Okay…"
…
A few more hours passed.
"F*ckk I'm so thirsty!"
"If you get out of this alive, remember to treasure water more."
"Hmpf. You seem unfazed by all this. Are you a robot? Do you not feel thirst or hunger?"
She had even eaten the chilies like they were just snacks, with no regard for saving food for later.
"I do. I'm just used to this. We don't have many of the luxuries we are having here, at the sea, you know?"
"Is that right…" He shuddered a little from the thought.
"If you are feeling more thirsty than hungry, then sleep might help. Just don't try to go to sleep if you're really feeling hungry."
"Sure, but not right now, I feel like I'm almost there! *Yaaawn*"
"You have been laying down for hours now. I can see you're exhausted. Don't push it too far."
"Yeah, yeah. I'll go get some sleep in a bit. I just want to try it a little more…"
…
Sai woke up the next day feeling like sh8t.
His stomach never hurt so much in his life, and his sweat covered his body. Aside from that, his head was throbbing even more than before. Nonetheless, no one would go save him, he had to solve the mechanism somehow.
'That bastard Viktor said they managed to clear it before. It couldn't have been a lie, right? If he lied, then that would mean they didn't manage to unlock this even after all that time of research, and we would be doomed.'
"Good morning Sai." Beidou scratched her butt and cleaned her eyes.
"Morning." He responded curtly.
"Hey, what's up with you? You falling apart already?"
"Don't bother me. I need to concentrate!"
"..."
Although he felt quite bad for saying that, his growing insanity wouldn't let him apologize.
'Concentrate! Concentrate! I need to concentrate! It doesn't matter if they did or didn't figure it out, I need to figure it out. There must be a pattern. Yeah, let's go look at it again.'
More hours passed by while Sai religiously studied the mechanism.
…
Beidou was sleeping silently when she felt tremors on the ground.
*Whoooom*
"Ha…HAHahaH- *cough*~*cough*- hAHAHaa! I did it- I did it!!!" His throat was extremely sore at this point.
She stood up and found Sai laying down beside the now shining cube. It had something like ancient characters hovering over it in a golden light. But most importantly, she saw the huge doors slowly opening up on their own.
He had started his research on the fact that the system was purely mechanical, or at least its activation. That was good for him, who couldn't use any kind of energy (electrical, elemental or who knows what else). The clinking sounds the cube made when it rolled were the guiding lines for his progress. There were many other patterns he found when turning it, and he took a while to group them into categories.
Sai based his analysis on the scientific method. Yes, the one they taught at the local school. But don't you underestimate it, for it provides the needed tools for any kind of non-systematic innovations one could think of. Coupled with his experience writing a pair of early-college-level physics papers, he devised something: a methodology for the validation of every action on that cube.
It was no easy feat. From beginning to end, there were almost no successful results to base any type of progression on. In other words, he didn't actually know with good certainty if he was getting anywhere. He only persisted through his belief in the scientific method.
Even after seeing the glowing characters that evidenced his success, Sai didn't know if his logic was right. He didn't know if the pattern he found was real or if it was pure coincidence. In fact, he didn't even know how he did it. But that didn't matter anymore, because he opened the doors. Everything else could be left for later.
"Finally, I did it…" Sai smiled widely.
Neither of them could fully believe what they were seeing, but relief washed over them at an incredible pace.
Beidou suddenly raised him from the floor, grabbed his head and gave him a smack kiss on the lips.
"You did it! Hahahah! You did it, Sai!" She started laughing intensely.
Sai was released and almost fell to the floor from the shock. He didn't even process the pain of having his wounded head grabbed by force. But the mood wasn't romantic at all, so he focused on the opening doors and laughed with her.
"Hahah… I did it, captain!"
"Hahahah!! This is crazy. I really thought we were goners for a second there, but good job, Sai."
Her phrase could have been somewhat offensive, but all he heard were flowers. A silly grin took place on his face.
Slowly but surely, the huge doors revealed what was inside. It was another room with a tall ceiling, gray and blue walls and the same architecture. But differently from the other, at its center, imprinted on the floor, stood something that could be described as a magic circle or rune. It shone in a lighter tone of blue light, a familiar one to Sai. Additionally, its engravings were also familiar.
"That circle…"
"Let's get inside, before we're stuck here again." Beidou urged.
"Yeah."
They entered the room and looked around with curiosity, it was the first new environment they saw for more than 24 hours. However, they soon lost their interest, it was the same as outside.
*Whoooom*
The doors startled them as they started to close, but none of the two made a move.
Once if fully closed, Beidou asked:
"So, what now?"
"I'm not sure, I think it may have something to do with this circle here."
"Makes sense." Beidou agreed and went up to it.
"Don't step on it yet, we don't know what it might do-"
He tried warning her but she paid no heed and directly stepped onto it. And as soon as both her feet were inside the circle, it glew, and Beidou disappeared out of thin air.
"..."
"Do I have to…? Dammit."
Notwithstanding, his hurting belly and dry throat forced him to follow her.
"Argh, c'mon. When can I take a rest?" Sai complained as he stepped onto the circle.