"Umbra" follows Kaien Voss, a young man haunted by recurring dreams of a burning city where an older version of himself stands amidst armies that call him "monster." Living in Veyral Village - a seemingly peaceful settlement protected by an ancient, mysterious barrier called the Veil - Kaien has been taught that the world beyond is nothing but darkness and death.

Everything changes when the Veil is shattered by the Iron Dominion, a conquering nation that launches a brutal invasion. In the chaos, Kaien's mother is trapped beneath rubble, forcing his father to drag him away as she sacrifices herself. The village falls. Thousands die. Kaien escapes with nothing but grief and a burning desire for revenge.