The Lair contains mostly Dragon Lords but also Dragons and Dragon Hatchlings. It is a great spot to hunt many Dragon Lords at the same time since the respawn is considerably large, which can be done using area spells. Mages frequently hunt here using Sudden Death Runes as well, using Magic Shield at lower levels to be protected from combos.
Because of the high number of Dragon Lords you should enter the lair with caution, and it's not recommended to go there alone if you can't handle more than 3 Dragon Lords at the same time. Most of the floor is covered on fire after the Server Save, and later from Dragon Lord's Fire Bombs if someone starts hunting, making a pair of Firewalker Boots very useful when hunting here.
To reach this Dragon Lair you will have to go through the first missions of the The Pits of Inferno Quest.