A nameless mercenary dies on the battlefield, his last regret that he could not become stronger. He awakens in a forest, reborn as a kobold—a small, fluffy, dog-like monster often dismissed as the weakest of all creatures. His new body is frail, his voice little more than a whimper, and his lifespan is a mere ten years. But he retains all the tactical knowledge and combat instincts from his past life, and he refuses to accept his fate.

The story unfolds in a fantasy world where monsters, humans, and demi-humans coexist in a harsh, survival-driven wilderness. The protagonist is initially part of a small, starving pack of kobolds. Using his human-era strategic thinking, he teaches them how to forage, set traps, and fight as a coordinated group. After a humiliating first defeat by a goblin, he analyzes the enemy’s weaknesses and leads his pack to a small victory, earning their trust. He names his most loyal followers: Gar, a sharp-eared scout; Mimi, a curious young kobold; and Don, a strong but timid brute. Through relentless training and clever tactics, the pack grows from a handful of survivors into a disciplined fighting force.

A central mechanic of the world is evolution. By gaining combat experience and achieving milestones, kobolds can evolve into more powerful forms—such as High Kobold, Combat Kobold, Scout Kobold, or even rarer variants. The protagonist pushes himself and his pack through repeated evolutions, each time gaining sharper claws, stronger bodies, and new abilities. The pack’s growing strength attracts other kobolds, swelling their numbers and allowing them to carve out territory in the forest.

Key narrative arcs include the defense of their home against a goblin army, where the protagonist uses guerrilla warfare and layered traps to overcome a numerically superior enemy. Later, an organized orc warband forces them to employ psychological warfare and starvation tactics. A turning point occurs when the kobolds encounter a human village under attack by bandits. The protagonist leads his pack to rescue the villagers, and a young human woman named Muriel becomes an ally. This first interaction with humans opens new possibilities and complications. Muriel aids the kobolds, but the party must eventually part ways as the protagonist decides to lead his pack south to find a more secure settlement.

During their journey, they rescue a cat-eared girl named Liz from goblin raiders. Liz becomes another companion, further expanding the group’s diversity. The story follows their continued growth, the evolving hierarchy within the pack, and the protagonist’s unyielding drive to climb the evolutionary ladder and claim the title of world’s strongest.