"Four mana points left at the end of the day," Elio calculated, checking his reserves. "Enough to breathe, drink water, and face any unforeseen event."
As the tunnel grew, Elio made a fascinating discovery. When he sealed the top, a small section of the tunnel inside the wall didn't completely fill with cores.
"Interesting," he murmured, observing how the cores stopped meters before reaching the tunnel's ceiling in that section.
This space became his refuge during rest periods, allowing him to sit on the accumulated cores without fear of being crushed.
To better understand the phenomenon Elio observed in his sealed tunnel, we could compare it to the functioning of a water seal in a modern toilet, although this concept didn't exist in Elio's world.
In a toilet, the water seal is a curve in the pipe that maintains a small amount of water, creating a barrier that prevents gases and odors from the drain from returning to the bathroom. Pure physics.
Similarly, the way Elio had built his tunnel created a space where cores couldn't completely fill due to pressure, forming a free space that provided him with a small refuge.
Elio, unaware of this comparison, simply appreciated the space that allowed him to rest without having to absorb the cores, seal the rear, or open more small holes.
In this small sanctuary, he began to spend more time interacting with his invocations.
"You know," Elio said one day, as he paused to rest his mind if not his body, "I wonder what the others are doing back in the city. Do you think they're worried? Or maybe they're just getting on with things, assuming I'll be back when I'm back."
Wide Guard trumpeted softly, as if in response. Elio chuckled, patting the elephant's trunk.
"You're right, buddy. No use worrying about that now. We've got a job to do."
The days turned into a monotonous but necessary routine. Build, seal, rest, repeat. To combat boredom, loneliness, and the growing sense of hunger, Elio alternated between his invocations, finding comfort in the company of his magical creatures.
"At least you don't need to eat," he joked with his ice penguin one day, his stomach growling in protest at the lack of food.
One day, he decided to summon his frog, a creature he had used little since obtaining it. The frog appeared with a soft "plop", looking at Elio with its large bright eyes.
Each invocation had its own personality and unique abilities.
Soak was playful and agile, able to find and point out the smallest drops of moisture in the tunnel. Iron Tail was cautious, its sharp hearing alerting Elio to any change in the sounds of the surrounding cores. Ice Ball, with its curious and aggressive nature, often made Elio laugh with its small charges as it slid at his feet.
"I don't know what I'd do without them... They make all this a little more bearable."
As the tunnel grew, meter by meter, day by day, Elio found himself developing a deeper bond with each of his invocations.
♢♢♢♢
Upon reaching around 150 hours, Elio paused to evaluate his progress. He had managed to build approximately 100 meters of vertical tunnel, an impressive feat considering the circumstances, but still far from the surface of the sea of monsters.
"It's time to rest and recover mana," he told himself, feeling the mental exhaustion of days of intense concentration.
Elio settled at the top of his carbon tunnel, his body heavy with the accumulated fatigue of days of incessant work. Although his mind was buzzing with anticipation of what was to come, he knew he needed this last rest to recover his mana.
Hunger gnawed at his stomach, a constant reminder that his time in the sea of monsters was reaching its limit.
"Just a little more," he murmured to himself, his eyes involuntarily closing. "One last effort."
Sleep enveloped him quickly, his body grateful for the brief respite. In his dreams, he saw fleeting images of the city, of his friends, of everything he had left behind. These visions only strengthened his resolution to return.
♢♢♢♢
When he woke up, Elio still felt hungry, but he was no longer sleepy and his mana was fully restored. Without wasting time, he began the final task: absorbing the cores that separated him from the bottom Locus of the sea of monsters.
This time, the absorption was different. He couldn't afford pauses or breaks. He needed to create a hole large enough for the monsters to descend and see the tunnel directly.
It was the moment of truth.