In the misty forests of medieval Norway, a Viking named Einar Bear-Friend forged one of the strangest bonds in Norse legend. When his crew found a slain bear and its orphaned cub, they wanted its pelt. Einar refused. “No warrior strikes one who cannot strike back,” he said — and carried the cub home. Fed on goat’s milk and raised by the hearth, the bear — Bjarki — grew massive and fiercely loyal. Together, they trained, hunted, and learned to move as one. When war came, Einar’s enemies trembled: