The Dagon'hai robe hat was released on 26 November 2008, as a part of the Grandmaster quest While Guthix Sleeps. It is part of the Dagon'hai robes set, which is level 40 Power armour. Players obtain one robe set from the quest. Players can also buy the hat from other players or get it as a rare drop from Dagon'hai Monks. These are the robes worn by members of the Dagon'hai (like Surok Magis). The Dagon'hai robes require 40 Magic and 40 Defence to equip.
It is not necessary to complete While Guthix Sleeps to wear these robes. However, it is required to defeat Bork to complete The Hunt For Surok miniquest, which is a prerequisite for While Guthix Sleeps.