One of the many threats Brynhild has to tackle with her magic on the Island of winds are the skuggabaldur creatures, or shadow cats.
Have you heard the Icelandic folktale of the skuggabaldur and the cat at Bollastaðir? Read on!
There is a tale of a skuggabaldur who was particularly harmful toward the sheep in the county of Húnavatnssýsla. The skuggabaldur was found in its burrow where a flock of men had cornered it and proceed to stab it. As the skuggabaldur was being stabbed it said “Tell the cat at Bollastaðir that skuggabaldur was stabbed today in the ravine.” The men found this very peculiar. Later that day, the man who delivered the final blow on skuggabaldur came to Bollastaðir, staying the night. That evening the man told the tale of his hunt as he lay on his bed. An old tomcat sat on a crossbeam above him. When the man recited the words spoken by the skuggabaldur, the tomcat leaped down upon the man grabbing hold of his neck using its sharp teeth and claws to lock on. The cat held on so tightly the only way it could be removed was by chopping off its head. By the time the cat was removed the man was long dead.
(Jón Árnason, Icelandic folktales and adventures I, p. 610.)