Goblin Slayer Gaiden: Year OneGoblin Slayer: Side Story Year One; Goblin Slayer! Side Story: Year One; Убийца Гоблинов: Год первый; ゴブリンスレイヤー外伝：イヤーワン; 哥布林殺手外傳：第一年

A prequel series that reveals Goblin Slayer's past and the events that led him to become an adventurer with the sole purpose of exterminating all goblins from the world.