The "Zulu Warrior" song has been used as a down-down song. There are two or three drinking traditions related to the song.
The song has been used as the down down for a "Dirty Pint" tradition (various top shelf liquor topped with stout). Other items for the "dirty pint" are reported. One became a Zulu warrior by drinking that in one go without getting sick.
Another tradition, one becomes a Zulu Warrior by sticking toilet paper up one's buttocks, lights it on fire and needs to finish a pint of beer before the toilet paper burns you up. This tradition is also called "Flaming Assholes". After this you are a Zulu Warrior.
The song is used to sing to those on tour. After they get their first try (score) while on tour, the Zulu Warrior song is sung to the person after the game they are expected to strip naked and run around the field.