The Valknutr is a This symbol consisting of three interlinked triangles. The symbol can be drawn either as three distinct triangles or as a single twisted band (“unicursal”). The name comes from the same source as valkyrie – the Norse word valr, fallen warriors.
The Valknut is the “Knot of the Slain” because Odin’s followers tend to die violent deaths. Odin’s followers don’t die violent deaths because of the Valknut. They die violent deaths because they follow Odin, and the only way to get into Odin’s hall, Valhalla, is to die in battle.