The Mask is given to Link by the Gorman Brothers. To obtain it, he must go to the Gorman Track once he has Epona, and ask to race against them for 10 Rupees. If Link wins, they will award him with the Garo's Mask.

Wearing it allows entry into Ikana Canyon, as well as the ability to encounter and battle Garo Ninjas. If defeated, the Garo Ninja will reward Link with a tip that may help him on his quest.

If a ReDead sees the Mask, it will start dancing, allowing Link to walk past it without being attacked.

Nintendo 64 Garo's Mask