 Heimdallr requires less sleep than a bird, can see at night just as well as if it were day, and for over a hundred leagues.Heimdallr's hearing is also quite keen; he can hear grass as it grows on the earth, wool as it grows on sheep, and anything louder.Heimdallr possesses a trumpet, Gjallarhorn, that, when blown, can be heard in all worlds, and "the head is referred to as Heimdall's sword".