Tradition: Polish Mythology
Alternative Names: Kasny
Category: Snake

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The Myth

Kasny were disgusting, serpent-like creatures that fed upon the blood of their victims. Alone they were relatively harmless, but when they attacked in groups they became deadly. A whole swarm would throw itself upon a person from every direction, biting relentlessly and fastening onto every part of the body like leeches.

Once they began feeding, the Kasny would fall into a frenzy. They attacked with savage determination, sucking up their victim’s blood while paying no attention to the wounds inflicted upon them in the struggle. Their hunger was so intense that they continued attacking even when seriously injured.

Sometimes a Kasny became so swollen with the blood it had consumed that it died together with its victim. Only the strongest individuals were capable of surviving such an attack and retreating once again into their hiding places.

This suicidal manner of feeding fortunately meant that Kasny remained extremely rare creatures. Their greatest danger came not from a single creature, but from the sudden appearance of an entire swarm, descending upon a victim and overwhelming them through sheer numbers.

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Sources

Zych, Paweł, and Witold Vargas. Bestiariusz słowiański. Część pierwsza i druga. Warsaw: Bosz, 2017.

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