It is thought that the Aztec Whistles of Death were used used in a few locations across ancient Mexico. The reason why death whistles were created, sadly, has been lost to history.
Examples of the death whistle have been found at the Ehecatl temple at Tlatelolco. Ehecatl is a wind god and the association with a whistle seems strong.
In Pure Spirit
If you had the chance would you listen to an old wizard play the death whistle?