”I invite you to a game that never ends.” — If you saw a sentence like this, what would you do? Normally, one would be suspicious, but the protagonist of this story, Yamada Kenichi, is different. Despite being a 35-year-old salaryman, he is a hardcore gamer who loves ”completionist grinding” more than anything and has absolutely no interest in games that can be cleared easily. When he happens upon a mysterious online game without even a name, he chooses the highest difficulty, ”Hell Mode,” without hesitation — the interesting part is that the direction of the story is already clearly shown at this point.

Before he knows it, Kenichi disappears and begins living as ”Allen,” a serf boy in another world, but what is decisively different here from many other isekai works is the severity of the environment. There are no developments like the so-called ”reincarnated and immediately overpowered”; rather, the starting point is near the very bottom. In a situation where even eating is not easy, the reality of having to move forward one step at a time feels exactly like the ”Hell Mode” he chose himself. As a reader, the harshness is so intense it makes you want to doubt, ”Is this really a game?”, which conversely heightens the immersion into the story.

In such a harsh world, what Allen obtains is the unique ability of a ”Summoner.” However, this is also troublesome; rather than a convenient cheat ability, it is closer to an ”unknown system with no idea how to use it.” There are no manuals or walkthrough sites, and he has no choice but to understand it bit by bit through repeated trial and error. This process is depicted very carefully, and I feel the great charm of this work lies in the emphasis placed on the process of ”how to become strong” rather than just the result of ”becoming strong.”

What is particularly impressive while reading this work is that the protagonist’s thinking is thoroughly from a ”gamer’s perspective.” Efficiency, verification, repetition — the way he breaks through situations through such accumulation has a reality that can only be depicted by someone who has spent long hours deeply engaged in gaming. Moreover, because this functions not as mere self-satisfaction but as a means for survival, it possesses a tension and persuasiveness unique to this work.

In recent isekai works, there are many developments where a protagonist with overwhelming power from the start plays an active role, but this work draws a line between itself and that trend. Strength is not something given, but is depicted as an ”arrival point” beyond accumulation, so each and every bit of growth carries significant weight. That is precisely why there is a sense of accomplishment even in moving forward just a little bit, and I think that leads to the reader’s satisfaction.

There is no lie in the title ”Hell Mode”; this work is a story that consistently faces ”harshness” from beginning to end. However, that very harshness is the source of its interest, and precisely because progress isn’t easy, one becomes curious about what happens next. The composition, which charms through steady accumulation without relying on flashy direction or plot convenience, must be an irresistible attraction for readers who love completionist grinding. I felt it is a work with such addictiveness that the more you read, the more you want to see how strong he can become in the future.