While watching Konosuba I came across following sentence:
「我が真紅の流出もて 白き世界を覆さん」
What troubles me is the 「覆さん」. The translation used an imperative here, what fits most of the other spells in the series as well; however I don't know how this ending can be an imperative. I've read this post (Meaning of ぬ added to 連用形 / masu-stem, as in 風立ちぬ) already and assumed that in above stated sentence the general idea is the same. Nevertheless before I start making wrong suggestions I would like to know what grammar works behind 「覆さん」as an imperative (if that is even possible).
