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[Other] A monstrous animal that guarded Tuonela, the land of the dead. The monster was perceived with ever-open jaws, ready to catch and devour humans with frightening speed. Thus he became the personification of sudden death. Surma was also seen as a guard who prevented the dead from leaving Tuonela, rather than stopping the living from entering. Surma also guarded the house of Kalma, the goddess of death.

See more at Wikipedia.org...

[Other] A monstrous animal that guarded Tuonela, the land of the dead. The monster was perceived with ever-open jaws, ready to catch and devour humans with frightening speed. Thus he became the personification of sudden death. Surma was also seen as a guard who prevented the dead from leaving Tuonela, rather than stopping the living from entering. Surma also guarded the house of Kalma, the goddess of death.