This x4 instanced raid zone will be released with GU56. The entrance is assumed to be on the Erollis Dock in Frostfang Sea at -321,26,311 . Speak with Snarf Frostfoot at 174, -37, -1312 to get started!
The final boss has a challenge mode and should be very tough! In the normal mode you challenge him you do not attempt to kill him. The normal mode is considered cannon to the story.
Head on down the chimney again, see what lurks within...