Yama
In Mahabharata
Yama is one of the four Dikpalakas - the others being Indra, Varuna and Kubera. He is also lord of death.
Yama Sabha
Yama Sabha is described by Narada to Yudhishthira when the former visited Maya Sabha at Indraprastha. Narada says,
"The assembly house of Yama, the son of Vivaswat, was built by Vishwakarma. Bright as burnished gold, that assembly house covers an area of much more than a hundred yojanas. Possessed of the splendour of the sun, it yields everything that one may desire. Neither very cool nor very hot, it delights the heart. In that assembly house there is neither grief nor weakness of age, neither hunger nor thirst. Nothing disagreeable finds a place there, nor any kind of evil feelings there. Every object of desire, celestial or human, is to be found in that mansion. All kinds of enjoyable articles, as also of sweet, juicy, agreeable, and delicious edibles in profusion that are licked, sucked, and drunk, are there. The floral wreaths in that mansion are of the most delicious fragrance, and the trees that stand around it yield fruits that are desired of them. There are both cold and hot waters and these are sweet and agreeable.
In that mansion many royal sages of great sanctity and Brahmana sages also of great purity, cheerfully wait upon, and worship Yama, the son of Vivaswat. Yayati, Nahusha, Puru, Mandhatri, Somaka, Nriga; Trasadasyu, Kritavirya, Sautashravas; Arishtanemi, Siddha, Kritavega, Kriti, Nimi, Pratarddana, Shibi, Matsya, Prithulaksha, Vrihadratha, Vartta, Marutta, Kushika, Sankashya, Sankriti, Dhruva, Chaturashwa, Sadaswormi and Kartavirya; Bharata and Suratha, Sunitha, Nishatha, Nala, Divodasa, and Sumanas, Ambarisha, Bhagiratha; Vyashwa, Vadhrashwa, Prithuvega, Prithushravas, Prishadashwa, Vasumanas, Kshupa, and Sumahavala, Vrishadgu, and Vrishasena, Purukutsa, Dhwajin and Rathin; Arshtisena, Dilipa, and Ushinara; Aushinari, Pundarika, Sharyati, Sharava, and Shuchi; Anga, Rishta, Vena, Dushmanta, Srinjaya and Jaya; Bhangasuri, Sunitha, and Nishada, and Bahinara; Karandhama, Balhika, Sudymna, and Madhu; Aila and Maruta; Kapota, Trinaka, and Shadeva, and Arjuna. Vyashwa; Sashwa and Krishashwa, and Shashabindu; Rama the son of Dasharatha, and Lakshmana, and Pratarddana; Alarka, and Kakshasena, Gaya, and Gaurashwa; Rama the son of Jamadagnya, Nabhaga, and Sagara; Bhuridyumna and Mahashwa, Prithashwa, and also Janaka; king Vainya, Varisena, Purujit, and Janamejaya; Brahmadatta, and Trigarta, and king Uparichara also; Indradyumna, Bhimajanu, Gauraprishta, Nala, Gaya; Padma and Machukunda, Bhuridyumna, Prasenajit; Arishtanemi, Sudymna, Prithulaushwa, and Ashtaka also; a hundred kings of the Matsya race and hundred of the Vipa and a hundred of the Haya races; a hundred kings of the name of Dhritarashtra, eighty kings of the name of Janamejaya; a hundred monarchs called Brahmadatta, and a hundred kings of the name of Iri; more than two hundred Bhishmas, and also a hundred Bhimas; a hundred Prativindhyas, a hundred Nagas, and a hundred Palasas, and a hundred called Kasa and Kusa; that king of kings Shantanu, and your father Pandu, Ushangava, Shata-ratha, Devaraja, Jayadratha; the intelligent royal sage Brishadarva with his ministers; and a thousand other kings known by the name of Shasha-bindu, and who have died, having performed many grand horse-sacrifices with large presents to the Brahmanas--these holy royal sages of grand achievements and great knowledge of the Sastras, wait upon, and worship the son of Vivaswat in that assembly house.
Agastya and Matanga, and Kala, and Mrityu (Death), performers of sacrifices, the Siddhas, and many Yogins; the Pitris (belonging to the classes--called Agniswattas, Fenapa, Ushampa, Swadhavat, and Berhishada), as also those others that have forms; the wheel of time, and the illustrious conveyer himself of the sacrificial butter; all sinners among human beings, as also those that have died during the winter solstice; these officers of Yama who have been appointed to count the allotted days of everybody and everything; the Shingshapa, Palasha, Kasha, and Kusha trees and plants, in their embodied forms, these all wait upon and worship the god of justice in that assembly house of his. These and many others are present at the Sabha of the king of the Pitris (manes). So numerous are they that I am incapable of describing them either by mentioning their names or deeds. The delightful assembly house, moving everywhere at the will of its owner, is of wide extent. It was built by Vishwakarma after a long course of ascetic penances. Resplendent with his own effulgence, it stands glorified in all its beauty. Sannyasis of severe ascetic penance, of excellent vows, and of truthful speech, peaceful and pure and sanctified by holy deeds, of shining bodies and attired in spotless robes, decked with bracelets and floral garlands, with ear-rings of burnished gold, and adorned with their own holy acts as with the marks of their order, constantly visit that Sabha. Many illustrious Gandharvas, and many Apsaras fill every part of that mansion with music; both instrumental and vocal and with sounds of laughter and dance. Excellent perfumes, and sweet sounds and garlands of celestial flowers always contribute towards making that mansion supremely blest. Hundreds of thousands of virtuous persons, of celestial beauty and great wisdom, always wait upon and worship the illustrious Yama, the lord of created beings in that assembly house. Such is the Sabha, of the illustrious king of the Pitris!"