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Darkness Sword is a skill that has never made an official appearance in the Fire Emblem series--Fire Emblem: Genealogy of the Holy War, the only time it appeared in a game's coding, had the Darkness Sword skill go unused.
Darkness Sword is a skill that, when triggered, multiples damage dealt by the user's strike by 1, 2, or 3, and may also reduce damage dealt to the user by 20. Based on its name, it may have been intended to be one of the "Sword skills" and thus have been restricted to the Myrmidon and Thief promotion lines as well as Dancers.
| Genealogy of the Holy War
|| Multiplies any damage dealt by the user by 1, 2, or 3, and may also reduce damage dealt to the user by 20.
Genealogy of the Holy War
|| Only accessible via hacking
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