Koschei the Deathless

Koschei the Deathless is a figure from Slavic folklore, often depicted as an immortal antagonist. His defining trait is his immortality, maintained by hiding his soul—often in a needle, which is kept in a magical or hidden object, such as an egg, a chest, or a bird's nest. As long as this object remains intact, Koschei cannot die. Heroes typically seek to defeat him by locating and destroying his soul container. Koschei embodies themes of death, rebirth, and the peril of invincibility, representing an almost unstoppable evil that can only be overcome through cleverness and bravery.