Except where noted otherwise, the walls are made of rough stone blocks, irregular in size and shape, though generally rectangular, but fitted together tightly. The floors are made of large rectangular stones, similarly fitted together. In most areas the ceiling height is twelve feet.
Level 1 directly connects to Level 2 of the Upper Dungeons, the Ground Level and the Rat Warrens of the Inner Ward, the Lower Level of the Outer Ward, and Area 22 of The Grounds.
Three factions are contesting over control of this level: the xvarts, yvarts, and zvarts. All three of these goblinoids are in open warfare with the others and there is considerable animosity between the groups. In addition there is a special 'unholy' area within the level where several undead can be found. These are described below.
XVARTS. The xvarts reside in Rooms 21 to 27. While it would be possible to treat with the xvarts, their distrust of men and chaotic nature makes them treacherous allies at best. The xvarts believe that they have an advantageous position compared to their rivals due to their alliance with the Rat King of the Rat Warrens. The xvarts are not terribly well organized, but if attacked multiple times, they will make some preparations to deal with invaders. These will include adding guards to chokepoints, preparing barricades, and sticking together in larger numbers. If taking heavy losses, it is possible they will relocate to the Rat Warrens.
YVARTS. The yvarts are perhaps most amenable to overtures by adventuring parties. They have recently lost their leader in combat and have no strong allies or mercenaries to rely upon. If facing destruction by repeated attacks by an adventuring party, the yvarts will respond by making new traps and perhaps seeking alliance with the zvarts, although their hatred of this latter group makes this a last-ditch ploy.
ZVARTS. The zvarts believe they have a strong position, and it may take considerable negotiation to allow them to accept a treaty with adventurers. If they feel they are fighting a losing effort and given time, they will close portcullises, set more traps, and hire more Yellow Fang gnoll mercenaries from Level 2 of the Upper Dungeons.
If adventurers do come to an understanding with the xvarts, yvarts, and/or zvarts, each group will try to convince the characters to eliminate their rivals. They can offer guides and maybe a few warriors in exchange. They will not recklessly follow the adventurers into combat unless they believe that they have much more to gain than to lose by this behavior.
UNHOLY AREA. The stairs near Rooms 28 and 32 are each five feet high, meaning this portion of the level is raised above the surrounding areas. Paladins and good clerics will feel a tingling up and down their spines when entering this area. All clerics and paladins function at two levels lower when attempting to turn, destroy, or control undead here.