The forest spanned for who knows how long. It kept on going and going. It wouldn't be called 'Uncrossable' if one could just cross it by walking through.

Edward and Robert moved through the forest at a fixed pace. They moved at a pace that was neither too fast nor too slow. They had more than six months before they had to return to the academy for the Four Great Academy Tournament, so they decided to use this entire time to investigate the forest as much as they could.

The Uncrossable Forest was an incredibly dense forest. Even during the daytime, almost no sunlight could enter the forest. The deeper you go, the denser the forest and the darker it is. Once inside, one cannot tell time, or even guess how long they have been there for. Even one's sense of direction gets messed up after going deep enough.

"So, what's the plan?", Robert asked.

"I have brought a color-changing spiritual paper with me. It changes color every 24 hours. With the help of that paper, we can tell how many days we have ventured. My plan is to keep moving deeper for two months, then based on our situation, we will decide whether to move forward or come back."

"Ok then.", Robert nodded.

"Right now, the color-changing spiritual paper is blue. After one day passes, it should turn red, then after another day, it would turn blue once again. It keeps switching colors like that. When I saw the description of this paper in a book in the academy library, the idea struck me that I could use it in such a way when I enter places like this.", said Edward.

As they were talking, they kept moving inside the forest, going deeper and deeper. Slowly, time passed. As they moved deeper, they could only see trees and wild vines, nothing else. They kept moving in a fixed pace that was neither too fast nor too slow while checking the surroundings. As time passed, the color-changing paper finally turned blue.

"An entire day has passed. Yet, we don't see anything. Where are all the threats that were supposed to be here? Where were all those mysterious things that supposedly take down the king's army?", Robert was frustrated as they found nothing.

"Yes, I've been wondering about that too. But don't you think it is quite strange?", Edward asked.

"What is?", Robert didn't get it at first.

"If it was any other forest, even if we didn't come across Graded ferocious beasts, we would at least see ordinary non-graded wild beasts. But here, we haven't seen a single living thing, not even birds or insects.", Edward pointed out.

"Now that you mention it, I really find it strange. Where did everything go? It's as if nothing but the forest exists here.', Robert said.

They stopped moving and stood there to inspect their current surrounding.

"While we were moving, after reaching a certain point in the forest, I felt like we were moving around the same surroundings, yet I could not find any clues. One moment it felt like we had already passed a tree, yet looking closely, I find the trees to be different.", Robert suddenly said.

"What? You are feeling the same way too? I thought I was just confused by the terrain and overthinking things!", Edward shouted out just as he heard Robert's words.

"That means there is some truth to this speculation.", Robert said.

"Yes. Well, change of plans. While moving forward, I will leave a slash mark on the trees along the way with my ax. I am already in the Shell Shattering realm, and I can release physical essence out of my body. So, using mid-ranged flying slashes won't be tough for me, and it wouldn't even slow us down.", Edward declared.

"Ok.", Robert nodded.

This time, as they moved forward, Edward left slash marks on the trees along the way. The kept moving forward like this, and they went on for quite a while.

"Are we on the correct path this time?", Robert asked.

"I can't say. We should be on the correct path, but somehow I still feel like we are moving around the same path.", Edward replied.

"Maybe it really is because of the terrain?", Robert said.

"I'm not sure. Maybe you are right." , Edward was confused.

Suddenly, Edward stopped in front of a large tree.

"This tree!", Edward shouted.

"What is it?", Robert also stopped and came forward to check.

"I'm sure that we have definitely passed this tree. I even remember leaving a mark on its body. But now, there's no mark there.", Edward exclaimed.

"How can that be?", Robert was shocked.

Edward also had no idea what was going on. he moved around and checked the tree more and more. The more he checked, the more he became sure that they have passed this tree already.

"Wait, let me try something.", Edward suddenly said. He used one of his axes to slightly cut on the tree trunk.

The cut mark was shallow, as per Edward's intention. Green, slimy sap was coming out of the cut mark. Edward did not move and slowly observed the cut mark. After a while, the green sap was absorbed by the tree trunk like sponge absorbing water. Just after that, in visible pace, the tree started healing itself, and the cut mark became thinner and thinner. Soon, the cut mark completely disappeared without leaving a trace. It seemed as if there was never a mark there before.

"so, that's what's going on! The trees are healing themselves, so we thought we were seeing different trees but they were the same.", Edward finally realized.

"Then what do we do now?",Robert asked.

"Don't worry. I've figured things out. Although the trees heal themselves. Even the shallowest of wounds take a minute or two. This means if we leave a mark deep enough, it would take a long time to heal, and we can identify trees we have already passed by and avoid moving around in circles in the same place."

"Great idea! As expected from you!.". Robert praised.

"Enough with the flattering. Keep that to yourself till we succeed in moving forward.", Edward scolded.

Robert nodded. They had still many unknown troubles waiting ahead. The Uncrossable Forest was vast and mysterious. Who knows how many more horrifying secrets it was hiding?