SSS Doomsday Guide in the Apocalypse

For sixty-seven years, the remaining human population has been hiding behind the walls of Sealed Cities, witnessing their numbers decline due to the unyielding apocalypse. Their only chance for survival lies in the annual Expeditions, which consist of desperate, suicidal missions launched into the toxic wastelands of the apocalypse to locate the Source or gather clues to put an end to the apocalypse. To endure, members of the Expedition must risk their very humanity. By consuming the cores of apocalyptic monsters, they trigger unstable, superhuman mutations, but this power comes with a horrifying price; if one's body cannot manage the mutation, they will transform into one of the monsters themselves. Gio refuses to spend his last days awaiting a peaceful death. Thus, he volunteers for Expedition 67, joining a doomed team of cast-off citizens. However, when Gio ingests his core, he does not awaken a typical superpower mutation like the rest of humanity. Instead, he Awakens a System. Given a mysterious Guide interface that includes quests, a shop, and a concealed overarching goal, Gio defies all the rules of their shattered world as he begins with a modest ability [Command (E-Rank)], which enables him to control insects and small creatures, but the potential for growth is boundless. Equipped with his new System and abilities, Gio ventures into the unknown alongside Mel, a girl fiercely determined to carve out her own future, and a group of outcasts each burdened with their own heavy regrets. Together, they confront impossible landscapes, remnants of the old world, and terrifying creatures spawned from the apocalypse. Yet, as Expedition 67 delves deeper into the ruins of Earth, they gradually unveil a chilling truth. The Source of the apocalypse is not the mindless monstrosity that humanity has come to believe. The previous sixty-six Expeditions did not fail by mere chance. And the enigmatic force that is shattering their world is linked to a secret far more devastating than any of them could have anticipated. With time slipping away and the persistent threat of monstrous corruption hanging over them, Gio and his team must face the reality behind the apocalypse. Because this time, they may be battling for more than just survival in the Apocalypse.