When you hear “a protagonist who saves the world,” what kind of person do you imagine? A hero with a strong will, surrounded by comrades, who majestically faces any crisis? However, “Snowball Earth” takes that image in a slightly different direction. Yabusame Tetsuo, the protagonist of this work, is a person who is revered by humanity as a savior, yet he is incredibly shy around people. Even though he possesses enough power to protect the world, he doesn't know how to close the distance with others. Just having such a person as the protagonist makes you somewhat intrigued. And the moment you realize that his only friend is a giant robot named Yukio, it makes you feel that “this is different from your ordinary robot manga.”

The beginning of the story sets into motion from a situation that can only be described as utter despair for humanity. In 2025, galactic kaiju invade from space, bringing a crisis that attempts to destroy all life on Earth. A robot called Snowman was developed there, but this robot is far from ordinary. Despite originally being a weapon meant to charge at enemies and self-destruct, it objects on its own, protesting that it “violates robot rights,” and refuses to self-destruct. This point alone is quite striking. In standard robot works, “receiving orders and deploying” is the staple, but in this work, the robot side suddenly argues back. And the one who saved Yukio like that was Tetsuo, who was still only 9 years old. From that moment of promising to “make it so you don't have to die,” their relationship became not one of a weapon and a pilot, but of true friends.

The story progresses as they continue to fight the kaiju, and Tetsuo and Yukio grow as the hope of humanity. A robot that gets stronger, a boy expected to be a savior—hearing just this part makes it sound like a classic coming-of-age growth story. However, “Snowball Earth” suddenly shows a heart-wrenching development from there. When facing the enemy's main force of twenty thousand beasts in the final battle, the war situation rapidly collapses, driving them into a desperate state. Covered in wounds, the two resolve to self-destruct, but there Yukio ejects Tetsuo and chooses to remain behind alone. The words, “When you return to Earth, I want you to make lots of friends and be happy,” feel surprisingly heavy despite being a very quiet line. Even though a battle between giant robots is supposed to be what is depicted, before you know it, what remains in the reader's heart is not the combat scenes, but the parting between friends.

And from here, the story begins in the truest sense. Eight years later, the Earth to which Tetsuo returned after waking up from cold sleep was not the hometown he once knew. Stretching out there was a “global glaciation” covered in snow and ice—a Snowball Earth. This development is an extremely interesting part. Normally, a peaceful future would seem to await after the final battle, but this work begins a journey into an unknown world from that point. The readers also start walking without understanding the situation, just like Tetsuo. Questions pop up one after another, such as “Why did the Earth become like this?”, “What happened to humanity?”, and “Can the promise to Yukio be fulfilled?”, and your hand just won't stop turning the pages.

Looking only at the surface, “Snowball Earth” lines up grand elements such as “sci-fi,” “kaiju,” and “robot action.” However, as you read on, a charm that cannot be explained by those alone becomes visible. The center of this work might surprisingly be “human connection.” There is a mysterious warmth in seeing a boy who is shy and has no friends walking forward with the promise to his one and only friend in his heart. Although a colossal battle and a world-scale crisis are depicted, what lies at the core of the story is a very small and very precious promise.

What I felt after reading this work was that it made me reconsider the meaning of the word “classic” or “royal road.” While using staple elements like robots, kaiju, and an apocalyptic world, overlapping them with the friendship between a shy boy and a robot creates a surprisingly fresh atmosphere. And before I knew it, I found myself thinking, “Will Tetsuo be able to make friends?” rather than “What will happen in the next battle?” There are countless stories about saving the world, but there are not that many works that depict the loneliness after saving the world. That is precisely why I think “Snowball Earth” is a work that keeps lingering in your mind for a while even after you finish reading it.