After Breaking Off the Engagement, the Immortal Ancestor Dominates the Apocalypse

When ancient cultivator Si Linyue fails her ascension tribulation, she awakens in a nightmare future where mutated beasts rule and spiritual energy is extinct. Her millennia of cultivation should make her invincible—but in this tech-driven apocalypse, her power registers as zero, marking her as a helpless civilian. Unable to awaken supernatural abilities like other survivors, she's dismissed as dead weight. Until her flying sword starts casually decapitating S-rank monsters. Now this 'powerless' girl must navigate a world that can't detect her true strength, all while ability users keep trying…