Dennis steps out of his quiet suburban home and immediately confronts the grim reality of the system apocalypse, finding a neighbor brutally slain in a pool of fresh blood on the sunny pavement. The terrifying atmosphere intensifies when a grotesque, child-sized goblin wielding a massive, rusty cleaver launches a sudden stealth attack from the shadows behind him. Instead of panicking like an ordinary civilian, Dennis unleashes his boosted Dexterity, leaping away with ridiculous speed, easily dodging the lethal blow, and effortlessly dispatching the creature with a single, precise stab of his katana. He soon encounters a trio of aggressive goblins and realizes that combat in this new reality is surprisingly predictable, resembling a low-level video game where enemies foolishly telegraph their every movement. By utilizing his environment, tripping his foes, and maintaining absolute composure, he systematically dismantles the entire group without taking a scratch, feeling a strange metaphysical weight transferring into his own body with each kill. This easy victory boosts his confidence to dangerous levels, convincing him that he is a natural prodigy destined for greatness. Armed with his taped-up sheath and an unyielding grin, he continues his trek down the deserted, body-strewn streets toward the local park, eager to find more monsters to feed his growing addiction to speed. The thrill of the grind completely eclipses the horror of a collapsed civilization as he marches forward, completely unaware of the massive scale of the invasion or the dangerous entities waiting for him in the shadows. He hears the methodical, rhythmic echoing of gunshots ahead, signaling that other survivors have found their own overpowered methods of dealing with the green horde, but as he rounds the final corner he is stopped dead in his tracks by a sight that challenges everything he thought he knew about the limits of human potential, leaving him to wonder if he is truly as unique as he believes. He watches in utter amazement as a lone old man methodically empties magazines into an endless stream of spawning monsters, turning the park into a massive graveyard of green flesh.

At the park, Dennis meets Richard, an old veteran who is spawn-camping the goblins with a pistol, and his granddaughter Jenny, who assists by reloading magazines. Dennis is shocked to learn that Richard is already level four, having utilized the raw power of firearms to quickly accumulate experience points. Desperate to catch up, Dennis convinces Richard to let him farm the spawning goblins, demonstrating his bizarre, seemingly casual combat style that relies on pure speed rather than trained technique. He successfully levels up to two, dumping all his points into Dexterity, which makes his movements incredibly fast but temporarily disrupts his physical coordination. The survivors decide to abandon their position to seek a safer haven at a distant police station, planning a route that stops at a local gun shop to arm the rest of the group. Dennis tags along, refusing to use firearms to protect his speedster build from receiving gun-related skills, and instead acts as a scout and protector for the growing crowd of defenseless followers. As they travel through the quiet, body-strewn streets, the slow pace of the group frustrates Dennis, but he remains committed to his self-appointed role as a superhero. Upon reaching the gun shop, they find a scene of absolute carnage, realizing that the previous defenders were overrun by a massive horde of goblins. While the others argue about leadership and logistics, Dennis clears the building alone, finding only dead monsters and abandoned weapons, confirming that the threat is escalating far beyond simple skirmishes. Sitting on a crate of ammunition, Richard admits that their plan to reach the police station is likely a death sentence, forcing the group to make a painful decision that will split them in half and test the limits of their survival. The old veteran proposes a desperate trek toward a distant river fort, forcing the strong to choose between protecting the weak or leaving them behind to die in the ruins of the city.

The newly formed team of eleven capable survivors begins their arduous trek toward the fort, adopting a careful formation to avoid ambush. However, their precautions fail when a coordinated goblin strike catches them off guard, wounding Richard with an arrow and sending the group into absolute chaos. As savage monsters swarm the flanks, Dennis freezes momentarily, overwhelmed by the sudden violence and the realization that his companions are hopelessly outmatched in melee combat. The breakthrough occurs when he levels up mid-battle and is presented with a choice of skills, including the legendary Sword Saint passive. In a defining moment of self-actualization, Dennis rejects the temptation of becoming an overpowered swordsman, choosing instead to stay true to his speedster dream by selecting Heroic Dash, a unique skill that boosts his speed and mind when saving allies. This choice triggers a massive transformation, granting him superhuman perception that allows him to calculate the entire battlefield like a supercomputer. Moving as a blur of pure, physics-defying speed, Dennis darts across the street, intercepting lethal strikes, decapitating monsters, and saving his companions in a fraction of a second. The battle ends in a stunning victory, leaving the survivors in awe of his god-like abilities and cementing Dennis as their undisputed savior. Despite his physical exhaustion and the vomiting that follows his intense exertion, Dennis experiences a profound shift in his worldview, realizing that he does not need to wait for a magical threshold to become a hero. He embraces his role as the group's protector, commanding the survivors with newfound authority and utilizing a robust companion named Travis to carry him so he can rest his aching muscles. He begins to view the weak survivors not as a burden, but as a crucial project that defines his heroic identity, driving him to push his body past its physical limits to ensure they reach the safety of the fort before nightfall.

Upon reaching the fort, the survivors find it surrounded by hundreds of leveled goblins, rendering a direct assault impossible for their small group. Dennis devises a daring plan to abuse his system mechanics by using Lily, a young girl with a unique mind-bending invisibility skill, as a portable victim to trigger his Heroic Dash buff. By convincing his skill that Lily is in constant danger, Dennis activates his superhuman speed, transforming into a blur of death that clears half the horde in under a minute. However, his stamina fails him, his katana breaks, and he is brutally beaten by a massive, golem-like monster called the Arm of High Authority, barely surviving the encounter thanks to a last-minute rescue by his companions. After recovering in the fort, Dennis grows bored of the mundane routine and sneaks out to grind, eventually teaming up with Lily, who has been secretly sneaking out to level up her stealth abilities. They investigate a mysterious church surrounded by spatial cracks, which suddenly reacts to their presence and teleports them into a grey, silent mirror world that functions as a cosmic garbage dump. In this eerie dimension, they discover that their physical bodies do not require breath or food, but their existence is slowly being eroded by the aggressive nothingness of the void. Dennis defeats another Arm to gain massive experience, but realizes that his soul stat is blocked at zero, preventing him from utilizing magic or fully stabilizing his existence. He forms an uneasy alliance with Gareth, a half-insane, immortal hobo who has been stranded in the mirror world for weeks, and resolves to find a way to heal a critically wounded Lily and escape the dimension. The stakes escalate dramatically when a colossal, three-legged spider-like entity known as the Eye of High Authority descends from the sky, forcing Dennis to unleash his ultimate speed in a desperate bid to survive.