Heimdallr plays a critical role in Norse tradition as the guardian of the Bifrost, the rainbow bridge linking Asgard and Midgard. He possesses keen senses and is said to be able to hear the grass grow and see a hundred leagues away. Heimdallr is also prophesied to blow the Gjallarhorn to announce the onset of Ragnarök, the end times in Norse mythology, showcasing his vital function as a watcher and protector.