Koschei
In Slavic folklore, Koschei (Russian: Коще́й, Koshchey;, also Kashchei or Kashchey; Ukrainian: Кощій, Koshchiy; Polish: Kościej; Czech: Kostěj) is an archetypal male antagonist, described mainly as abducting the hero's wife. None of the existing tales actually describes his appearance, though in book illustrations, cartoons and cinema he has been most frequently represented as a very old and ugly-looking man. Koschei is also known as Koschei the Immortal or Koschei the Deathless (Russian: Коще́й Бессме́ртный, Ukrainian: Кощій Безсмертний, Czech: Kostěj nesmrtelný), as well as Tzar Koschei. As is usual in transliterations, there are numerous other spellings, such as Koshchei, Kashchej and Kaschei. The spelling in Russian and other Slavic languages (like Polish "Kościej" or Czech "Kostěj") suggests that his name may be derived from the word kost' (rus. кость, pol. kość) meaning 'bone', implying a skeletal appearance.
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