Summoned to another world alongside six others, Evan Cross is the one no one wants. While the other summoned receive dazzling gifts meant for glory, war, and legend, Evan is left with Aside—a skill so vague and underwhelming that even the ritual hall laughs at him. Labeled low value and quietly pushed aside, he is sent to Fort Calder, a brutal frontier stronghold where weak assets are expected to die usefully. But the frontier has no patience for pretty rankings. At Fort Calder, survival is decided in inches: a strike turned just enough, a breath kept steady under pressure, a fall recovered one heartbeat faster than death. As Evan trains under hard-eyed veterans and learns to drag meaning out of a skill everyone dismissed, he begins to discover that Aside can do something no one else's power can—it can add one more effect, one more correction, one more chance to survive. And on the frontier, one more chance can change everything. When Abyssal scouts begin probing the roads around Calder, hidden guidance trails appear in the eastern woods, and the ruins beneath the war zone start whispering of a forgotten battle art, Evan is forced into a conflict far larger than a single "useless" skill should ever matter in. Because if the kingdom's strongest heroes are blades, fire, speed, walls, and miracles, then Evan may be the one thing that lets those powers hold together when the real enemy arrives. The Leftover Summon is a dark fantasy progression adventure about an overlooked hero, a mocked skill that grows through relentless effort, and a war where the smallest advantage can decide who lives long enough to matter.