The Erebonian Curse (呪い or 帝国の呪い) is a curse that essentially stirs up hatred and fighting instinct within citizens of Erebonia, which in turn leads to greater destruction. Those with insecurities are at greater risk of succumbing to the curse, with Alan's desire to protect Bridget and Cedric's extreme inferiority complex being prime examples.
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The curse is spread throughout Erebonia and surrounding countries. The Great Twilight further amplifies its effects. In Trails of Cold Steel III, Finale: "For Whom the Bell Tolls", the Great Twilight was initiated through Giliath Osborne's ability to unify with the curse.
The curse not only affects people's thought, it also affects their fighting abilities. For example, the Iron Knights (Rufus Albarea, Lechter Arundel, Claire Rieveldt), the Imperial Defence and Alan have demonstrated increased fighting capabilities. Persons influenced by the curse have their eyes marked by some sort of crest. People who are afflicted by the curse are able to break out of it if they directly confront their insecurities, such as when Machias is able to make Arthur face himself and finally move past his fiancee's death.
Another effect of the curse is forcing selected people into specific roles. This 'compelling force of the curse' has robbed many Erebonians of their fate throughout history. One such victim is Ash Carbide, who was forced by the curse to pursue the instigator of the Hamel Tragedy which culminated in his attempted assassination of Emperor Eugent Reise Arnor III.
Victims of the curse include, but are not limited to:
- Rean Schwarzer has been a candidate for the curse ever since Giliath Osborne's heart was transplanted into his body. The curse's influence led to him triggering the Great Twilight and was later used as a spare when Osborne died.
- Ash Carbide was regarded as a Calvard spy who tried to assassinate the emperor, fuelling nation-wide animosity toward Calvard.
- Angelica Rogner was robbed of her free will and used as a pawn after being shot by Copper Georg.
- Victor S. Arseid was used by the curse as Erebonia's strongest swordsman and given the role to rise the curtain for the Third Rivalry by fighting Class VII. Unlike Angelica, he did not lose not his ego.