Axel did not tell others, but because of the system, he is able to see details of the crystal.

"Forbidden Crystal: En Block"

"When placed on an area, it will block the "En" discovery and search in an area of 15 km to 15 km in diameter."

"It cannot hide the area against Nen abilities, but only "En."

Axel knew that this crystal was not that important in his situation, but he knew that a lot of people would want it to hide something from NEN users in particular. It is true that it does not hide against abilities, but hiding against En is more of a generalistic protective approach.

In a sense, if Axel did not have Freedom Ability, the group would miss the throne room with ease as En did not work and they were not able to see anything more. This crystal was the reason why Axel En did not work as well as he expected and was not able to see the room hidden in the coffin.

At the same time, the system clearly shows that this crystal has no condition or backlash to its use, making it a Neen item with the ability to protect an area from En with no backlash. It definitely deserves something.

Axel pulled Navi to his side and whispered, "I think this crystal is what blocked my ability to discover the hidden door in the coffin room." Navi's eyes widened as she realized what he meant. "It's a nen item," she whispered back. "It must have been created specifically to block En abilities."

Axel nodded. "Exactly. And that means there's a good chance whoever created this item also created the hidden door. We need to find out who that is and how to bypass the crystal's effects."

Navi took a deep breath and closed her eyes, focusing her mind. After a few moments, she opened her eyes again and said, "I sense a strong aura coming from the north side of the room. It feels like it's coming from behind a wall."

Axel thought in his mind. "Crystal does not block any En or Nen abilities when they are used in the area the crystal hides from outside. Which means once a person has discovered and entered the area of protection of the forbidden crystal, it does not have any effect on the people or Nen users inside of that area.

"It is only to be expected that it works like this considering it does not have any conditions of use from what I can see."

"This kind of limitation may be added to it so that it can work continuously."

Axel nodded. "Let's go check it out." The group moved to the north side of the throne room and began searching for a hidden entrance. After a few minutes, they found a small crack in the wall that was barely visible. With some effort, they managed to push the wall aside and reveal a narrow passage leading deeper into the underground complex.

As they made their way through the passage, they came across several more traps and obstacles, but with their combined abilities and quick thinking, they were able to bypass them all. Finally, they came to a large chamber that was filled with strange, glowing symbols and crystals. In the center of the room was a tall, hooded figure that was surrounded by a pulsating aura.

Axel and Navi exchanged a look and then nodded at each other. They knew that this was the creator of the nen item that had blocked Axel's ability. Without hesitation, they stepped forward to confront the figure and demand answers.