Main Gate

If characters approach this area from the north, read:

A wide passage slopes down to a set of bronze doors. Coiled serpents decorate the metal, with a sliding hatch at head height. Four-inch-wide holes pierce the base of each door.

When opened, the bronze doors slide into wall niches to either side of the tunnel. To pull the doors apart, the yuan-ti broodguards under Nahth’s command tug on heavy chains on the south side of the gate. To bypass the doors without opening them, yuan-ti malisons transform into snakes and slither through the holes at the bottom of the doors.
A type 1 yuan-ti malison named Nahth (pronounced NAWTH) and four yuan-ti broodguards defend the main gate. Strangers are denied entry unless they are accompanied by one or more yuan-ti.
Nahth is greedy. After allowing characters to pass through the gate, he demands a bribe in the form of food (preferably meat) or treasure (minimum 10 gp). If the characters refuse to pay up, Nahth picks a fight with them. Combat here draws reinforcements from area 2.
Snake Pits
Beyond the main gate are three pits covered with iron grates. When enemies attack, the broodguards remove the grated covers and form up in a defensive line on the south side of the open pits. Each pit is 5 feet across, 10 feet deep, and filled with a swarm of poisonous snakes. The walls of each pit are too smooth to climb without the aid of gear or magic. A creature can skirt around the edge of a pit with a successful DC 10 Dexterity (Acrobatics) check but falls if the check fails. A creature can also attempt to clear the pits with a standing jump or running jump (see the Player’s Handbook for jumping rules), provided there are no broodguards lined up along the far side.
Treasure
Nahth has a crocodile skin pouch containing 28 gp and wears gold ceremonial bracers sculpted to resemble bats (150 gp for the pair).
Navigation
The Hallway to the east leads to Fenthaza's Quarters as well as the Sacrificial Chamber.

Type

Gatehouse