Since time immemorial, there have been hellish creatures that secretly prey upon the living of Equestria, However, Darkness exists because Light exists, and Light exists because Darkness exists. To combat this threat, a group of warriors was formed - they gave their very lives so ponies can live without fear and look forward to a brighter future, yet their feats and sacrifices were untold, for like the enemies they hunt, they too, operate in secrecy. Yet, despite their efforts, they cannot fully eradicate their enemies; if anything, there seems to be more and more of those monsters as time passed...

Today, one of the most talented amongst the warriors is none other than Twilight Sparkle. But how did she get involved with such a fate? Can she keep her secret mission from her new friends? Most importantly, can she learn the magic of friendship, and fulfil her dark responsibility at the same?

Inspired mostly by the Japanese series Garo, and some ideas/elements taken from Samurai Sentai Shinkenger & Magical Girl Lyrical Nanoha.