Travel to the Unknown

"In their freetime, Mark and Luke were two excursionists. They were great friends. Together, they managed to get to the top of Mount K2, a very renowned but dangerous trip.
One year, they unfortunately got very poor.
Both got fired and they didn't find another job to replace the one they had lost. They were desperate.
For two years, they lived in a state of complete poverty. Luke became even a beggar, but the little money he gathered was not enough for him to survive.
One evening, Mark found the solution to all their problems. He remembered he had read an announcement, telling that a strange creature was wanted. It lived in a frozen valley in the Himalayas, exactly near the dangerous K2. That creature had already killed many excursionists, and it was promised a reward for those who would find and capture it.
It was told to Mark by an old lady passing nearby that no one wanted to take the risk of finding that monster: its appearance was considerably more horrible than the one any human being could figure out. But in the end, since no one had ever survived to its encounters, the appearance of that mysterious creature was still unthinkable and unknown to every human brain.
Mark and Luke decided to take the risk and look for the monster. If they didn't try, they never could have gotten the promised fabulous reward. Their thirst for money was stronger than the fear of risking their lives. All in all, continuing to live in those terrible conditions was already like being dead. Therefore, death didn't scare them too much.
They prepared all the equipment for that dangerous trip, and one morning they took the path to go to Mount K2.
The first days on the K2 glaciers were marked by terrible weather conditions. They were also attacked by a group of mountain wolves. However, they miraculously managed to make them pull back.
It was only after two weeks of intense research that they caught a glimpse of an enormous bipedal creature. It was marching in large steps upon the frozen rocks of the mountains. It seemed to jump from one mountain to the other, as it was incredibily enormous. Seeing the size of that terrible monster of anthropomorphic aspect, even Bigfoot would get more and more pale.
Mark and Luke were petrified as the violent creature seized them in its hands. They lost consciousness.

Now, we are six men in this frightening cave, and we are all excursionists. Soon, none of us will remain.
The monster's diet consists of two human beings a day. It tied us with a rigid rope to the walls of the cave. It has arranged us in a row near his rudimentary dining table. Mark and Luke have just been the last meal of the creature. Even in these terrible conditions, they still had the time to tell me the story of how they got in the hands of the monster. Tears began to run down their cheeks while they narrated their last adventures in the mountains.
In this situation, I am determined to write, write and write. The rigid rope the monster blocked us with leaves our hands free, so I am taking advantage of this to write the story of those poor men.
I want to make them live again through my words, even if I am pretty sure that no one will ever read my last writings. These words will get buried in the snow forever, together with our souls."

The frozen paper came to Albert's hands. He managed to read it entirely, even if it had been a daunting task to do so, since many words were unclear or completely illegible.
By reading the last life moments of those men, he began to feel a deep pain in his chest and his hands started to tremble. He understood he was in a deadly place. He had a pen with him, as well. He needed to add a single sentence to the story of the unlucky men devoured by the creature: "if you ever get here accidentally, leave this place immediately".
He put the paper in a visible position, then he heard a loud sound of heavy footsteps approaching.
A giant figure appeared at the entrance of the cave.