Hell's Stag Settings
The campaign starts in the Lady’s Ward of Sigil. From there the players must find their way across the outer planes and down to Maladomini, the 7th layer of Baator. The description of Maladomini can be found by clicking on that link. The exact location of the Nalfeshnee’s citadel is unknown, but is said to be in one of the former Malagard cities.